Crop Science and Production Collection

Permanent URI for this collectionhttp://10.10.97.169:4000/handle/123456789/37

Browse

Now showing 1 - 20 of 32

Assessment and management of post harvest losses of fresh mango under small-scale business in Morogoro, Tanzania
(JAPS, 2011) Msogoya, T. J.; Kimaro, E. S.
This study was conducted to assess postharvest losses and the effect of shade during wholesale market and hot water treatments on storage of mango cv. ‘Dodo’. To assess postharvest losses, mature fruits were packed on semi-rigid bamboo cartons, loaded on a truck without separators in between cartons and transported from Mkuyuni ward to Morogoro urban, Tanzania. The effect of heat stress during the wholesale market was evaluated by storing mango fruits under the sun, woven polypropylene shade and black net shade at Sokoine University of Agriculture. Mango fruits dipped in hot water at 60° C for 10 minutes were compared with untreated ones as control. Results showed that the fruit total postharvest losses were 43.8 % with the wholesale market, transport and harvest stages accounting for 30.6 %, 10.6 and 2.6 % of the total losses, respectively. The main features of fruit deterioration during the wholesale market stage were softening and microbial decay each accounting for 50.7 and 39.6 % of the total losses within the stage, respectively. Microbial decays of 7.2 % and mechanical injuries of 2.0 % were the major features of mango fruit deterioration during the transport and harvest stages. Storing fruits for three days under the woven polypropylene and black net shades significantly reduced fruit postharvest losses by 52.7 and 38 %, respectively in comparison with fruit storage under the sun. Hot water treatment reduced the incidence of microbial decay by 85 % and improved fruit total soluble solids content by 15 % in comparison to untreated fruits. However, hot water treatment reduced fruit firmness and shelflife by 56.0 and 71.4 %, respectively. In the short term, wholesale traders are advised to store fruits under the polypropylene shade while in the long term, municipal and council authorities are argued to construct cold storage facilities for fresh fruits. Furthermore, farmers are advised to disinfect mangoes with hot water, especially those purported for immediate marketing.
Bacterial leaf spot of sweet pepper caused by Xanthomonads-. incidence, pathogen characterization, epidemiology and management options
(Sokoine University of Agriculture, 2011) William, Magdalena Nchagwa Magere
A study was conducted in sweet pepper growing regions (Morogoro. Arusha, Tanga and Mbeya) in Tanzania to determine incidence and epidemiology of bacterial leaf spot disease (BLS), characterize bacterial spot-causing xanthomonad (BSX) strains and screen for resistance of the locally available sweet pepper varieties. One hundred sweet pepper fields were surveyed and diseased samples were collected for laboratory analysis. Bacterial isolates were identified based on physiological, biochemical, PCR and pathogenicity tests. Races were determined based on compatible or hypersensitive response on differential sweet pepper near-isogenic lines ECW-10R, ECW-20R and ECW- 30R. Results indicated that, BLS disease was wide-spread in farmers' fields in the surveyed regions. Disease incidence ranged between 10—100%, while the overall mean disease incidence was 69.3 %. Disease severity was statistically significant on village basis and the overall mean score was 4.6. High mean disease incidence (93.3 %) and disease severity score (6.5) were recorded in Lukozi and Kivulul villages, respectively. The lowest mean disease incidence (12 %) and severity (1.2) were recorded in Utengule village. Poor cultural practices and epiphytic survival of BSX on host and non-host plants were found to be the sources of inocula for successive crops. The RST2/RST3 primer sets detected 59 strains to genus level and the effector/avirulence gene primer sets detected 68 out of the 74 strains tested. The species-specific primer sets identified 63 out of 68 BSX to species level and were pathogenic on the susceptible cultivar Early Calwonder (ECW). The BSX were X. euvesicatoria (30), X. perforans (10) and X. gardneri (23). Xanthomonas euvesicatoria and X. perforans dominated in Tanga region whereas Xanthomonas gardneri dominated in Arusha region. Five strains were not pathogenic on cv. ECW. Seven sweet pepper races (P0 - P6) were identified. Race P3 (50 %) dominated the strains of BSX in Morogoro, Arusha and Tanga regions. Race P6 (27.9 %) dominated in Tanga and Morogoro regions. Frequencies of races PO, Pl, P2, P4 and P5 were considerably low. All the locally available sweet pepper varieties were susceptible to BLS disease. This is the first report to characterize BSX of sweet pepper in Tanzania.
Banana xanthomonas wilt: occurrence and means of transmission in Kagera, Mwanza and Mara regions of Tanzania
(2016-02) Hashim, Ibrahim; Mabagala, Robert B
Abstract: Banana Xanthomonas wilt (BXW) disease is a major constraint of banana production in the Lake zone (Kagera, Mwanza and Mara) regions of Tanzania where banana plays an important role as a staple food and cash crop. Infected plants die and fruits rendered inedible. To assess the current status of BXW disease field surveys were conducted from December, 2011 to January, 2012 in Kagera, Mwanza and Mara regions. Twenty eighty banana samples with BXW disease symptoms were randomly collected from a total of 147 surveyed fields. Farmers’ knowledge of BXW disease was assessed using a checklist, discussions and direct field observations. Isolation of bacteria was done on Yeast Peptone Glucose Agar and identification was done based on morphological, biochemical and pathogenicity test. Results indicated that the incidence of BXW disease was highest (56.7 %) at Ihangiro and the lowest (10 %) at Ruhija and Mulela, in Muleba District; Nakamwa and Busagami, in Ukerewe District. Such results implied that, BXW disease is still a constraint to banana production in the surveyed districts. The results also indicated that BXW pathogen transmission was through infected farming tools (65.4 %) in Muleba District and infected planting materials in Tarime (50.5 %) and Ukerewe (45.8 %) Districts implying that these were the major means by which BXW disease was spread in the study area. About 58.33 % and 41.67 % of the farmers in Ibare and Kishanda villages, respectively, in Muleba District associated pied crow (Corvus albus L.) with the transmission of BXW causing pathogen. Results based on morphological, biochemical and pathogenicity test indicated that, four out of 16 bacteria isolated from infected banana samples were Xanthomonas campestris pv. musacearum (Xcm). Further studies on the relationship between the pied crow and Xcm transmission in Kagera, Mara and Mwanza regions, are recommended.
Comparative effectiveness of animal manures on soil chemical properties, yield and root growth of amaranthus (antaranthus cruentus l.)
(Sokoine University of Agriculture, 1999) Nonga, Dotto Leonard Mhoja
Pot and field experiments were conducted at Sokoine University of Agriculture (SUA), Morogoro, Tanzania during the 1997/98 cropping season. The study was carried out to comparatively evaluate the effectiveness of dairy cow, goat and poultry manures on soil available levels of N and P, amaranthus (Amaranthus cruentus L.) yield and root growth. In both experiments, the three amendments were applied at 100, 150 and 170 kg N/ha. The experiments were laid out in a split plot design, replicated three times with rates of application as mainplots and animal manure types as subplots. Pot experiment was conducted for a period of about one-month whereas field experiment was carried out over three crop cycles each lasting for about one month. The soil used in this study was classified as an Oxisol (Tropeptic Entrustax). Results of the glasshouse experiment indicated that applications of the three animal manures significantly (P < 0.01) increased soil available levels of N and P, amaranthus shoot dry matter yield, tap root length, root weight and tissue concentrations of N and P. These responses increased with increasing rate of application with the highest rate of application (170 kg N/ha) resulting in highest responses. Comparison of the responses from the three manures revealed that for all the parameters evaluated the trend was; poultry manure > goat manure > dairy cow manure. This trend was mainly due to differences in total N, total P, C/N and CZP ratios of the three manures. Poultry manure had highest levels of total N and total P and narrowest C/N and C/P ratios concurring with the superior mineralization of N and P observed and consequently, the highest responses in amaranthus yield and root growth compared to the other two manures. Results of the field experiment were essentially similar (except for the root growth which was not evaluated in this experiment) to those of the pot experiment. Soil available levels of N and P evaluated after first and third crop harvests were highest for poultiy manure followed by goat and dairy cow manures and the responses were highest after the third crop harvest suggesting that mineralization of organic forms of N and P increased with time. The above responses were significantly (P < 0.01) and positively correlated to amaranthus yield and tissue concentrations of N and P indicating that the observed response in amaranthus yield was largely due to soil availability and uptake of N and P. Based on the fertilizer recommendation of N and P for Southern Highlands of Tanzania (N= 40 kg N/ha and 20 kg P/ha) and the application rate of 170 kg N/ha used in this study, applications of 5.8 tons/ha of poultry manure, 9.8 tons/ha of goat manure and 13.4 tons/ha of dairy cow manure will meet the recommendation of 40 kg N/ha. The above application rates will also provide 30.5kg P/ha, 31.6 kg P/ha and 26.8 kg P/ha for the respective manures, which will suffice the P recommendation. Results of this experiment therefore, suggest that the three types of animal manures evaluated could substantially sustain crop growth in this soil and others with similar properties. The results should however, be confirmed under different field conditions and for much longer experimental duration.
Comparative effectiveness of animal manures on soil chemical properties, yield and root growth of amaranthus (antaranthus cruentus l.)
(Sokoine University of Agriculture, 1999) Nonga, Dotto Leonard Mhoja
Pot and field experiments were conducted at Sokoine University of Agriculture (SUA), Morogoro, Tanzania during the 1997/98 cropping season. The study was carried out to comparatively evaluate the effectiveness of dairy cow, goat and poultry manures on soil available levels of N and P, amaranthus (Amaranthus cruentus L.) yield and root growth. In both experiments, the three amendments were applied at 100, 150 and 170 kg N/ha. The experiments were laid out in a split plot design, replicated three times with rates of application as mainplots and animal manure types as subplots. Pot experiment was conducted for a period of about one-month whereas field experiment was carried out over three crop cycles each lasting for about one month. The soil used in this study was classified as an Oxisol (Tropeptic Entrustax). Results of the glasshouse experiment indicated that applications of the three animal manures significantly (P < 0.01) increased soil available levels of N and P, amaranthus shoot dry matter yield, tap root length, root weight and tissue concentrations of N and P. These responses increased with increasing rate of application with the highest rate of application (170 kg N/ha) resulting in highest responses. Comparison of the responses from the three manures revealed that for all the parameters evaluated the trend was; poultry manure > goat manure > dairy cow manure. This trend was mainly due to differences in total N, total P, C/N and CZP ratios of the three manures. Poultry manure had highest levels of total N and total P and narrowest C/N and C/P ratios concurring with the superior mineralization of N and P observed and consequently, the highest responses in amaranthus yield and root growth compared to the other two manures. Results of the field experiment were essentially similar (except for the root growth which was not evaluated in this experiment) to those of the pot experiment. Soil available levels of N and P evaluated after first and third crop harvests were highest for poultiy manure followed by goat and dairy cow manures and the responses were highest after the third crop harvest suggesting that mineralization of organic forms of N and P increased with time. The above responses were significantly (P < 0.01) and positively correlated to amaranthus yield and tissue concentrations of N and P indicating that the observed response in amaranthus yield was largely due to soil availability and uptake of N and P. Based on the fertilizer recommendation of N and P for Southern Highlands of Tanzania (N= 40 kg N/ha and 20 kg P/ha) and the application rate of 170 kg N/ha used in this study, applications of 5.8 tons/ha of poultry manure, 9.8 tons/ha of goat manure and 13.4 tons/ha of dairy cow manure will meet the recommendation of 40 kg N/ha. The above application rates will also provide 30.5kg P/ha, 31.6 kg P/ha and 26.8 kg P/ha for the respective manures, which will suffice the P recommendation. Results of this experiment therefore, suggest that the three types of animal manures evaluated could substantially sustain crop growth in this soil and others with similar properties. The results should however, be confirmed under different field conditions and for much longer experimental duration.
Control of cashew sucking bugs helopeltis anacard11 and pseudotheraptus wayi by manipulating the african weaver ants (oecophylla long1noda) populations in cashew nut trees
(Sokoine University of Agriculture, 2002) Mwinyi, Waziri Ali
Five field experiments were conducted during the 2000/2001 season at ARI-Naliendele. Mtwara region in southern Tanzania. The general objective of the study was to establish optimum population levels of weaver ants that will give effective control of Helopeltis anacardii and Pseudotheraptus wayi in cashew nut trees. The experiments were also conducted to establish the bionomics ofthe population of the cashew pests H. anacardii and P. wayi, and the predator. Oecophylla longinoda in relation to the antagonistic ant. Pheidole megacephala. Assessment of shoot and nut damage, and associated yield were carried out to establish the effectiveness of the predator against the two pests. The study has shown that high levels of O. longinoda had significant effects in protecting cashew trees from attack by H. anacardii and P. wayi Manipulation of number of nests of O. longinoda confirmed that 30 and 40 nests can provide maximum protection of cashew trees. The protective effect of the biological agent led to reduction of damage levels in shoots and nuts due to reduced number of pests and increased nut yield/tree. When the performance of the biological agent at different nest levels was compared to chemical control using lamda cyhalothrin (5 %). the chemical was found to be less effective as compared to cashew trees subjected to 30 or more O. longinoda nests. The antagonistic ant. P. megacephala. to the biological agent O. longinoda was successfully suppressed by Amdro bait. Reduction in population of the competitor ant resulted to increased numbers of (). longinoda in the field, and increased predation activity against the pests. Significant variations (P 0.05) of damage levels between trees subjected to weaver ants alone and those subjected to weaver ants in combination with Amdro bait were evident. Lowest damage levels were recorded in trees treated with Amdro bait in combination with weaver ants. It is concluded that weaver ants have a great potential for suppressing H anacardii and P. wayi to low uneconomic levels. However, for a successful establishment of weaver ants in the field, controlling of the antagonistic ants P. megacephala is essential.
Decomposition of crotalaria and leucaena green manures and their nutrient release patterns
(Sokoine University of Agriculture, 1992) Nikokwe, Chais Adam
The decomposition of Crotalaria and ochroleuca Leucaena leucocephala green manures. contained in litter bags and placed on the surface (8- 10 cm), was The study was or buried 12 weeks of incubation. studied during conducted under laboratory conditions determine and compare decomposition and patterns of the two of green manure subsequent nutrient in soil microbial determined and the release was manure residual nutrient release Changes investigated numbers with and decomposition on application to green manures. The effect of method related into the soil to decomposition. materials, and were time incubation Analyses of counting microbial were done at three week intervals. The rate of decomposition was expressed dry matter. organic carbon phosphorus in parameters the in terms of total nitrogen and residual material organic. All these were expressed as percentages of the original quantities added through the manure. Generally six weeks decomposition was fast during the first of incubation and slowed down thereafter rate of decomposition was similar in and decomposed by almost 50 and weeks of incubation, respectively. The both green manures, 70% after in six and 12 addition they had incorporated manure soil releasing capacities. However similar nutrient more decomposed faster and released nutrients than surface-applied. In treated microbial numbers incubation after The soil there during rapid were the first which populations soil-incorporated green microbial numbers than increases in weeks of six almost levelled off. manure resulted in the surface-applied one. Larger In the control soil such changes were small. From the that when results of used the this study two green it was manures z incorporated into the soil at least six period when the intended nutrients. crop has This will allow speculated should be weeks before the its maximum need for synchronization of maximum nutrient release with high nutrient demand by the crop.
Effect of fertilizer types and application rates on onion (allium cepa l.) Productivity in Kilosa district
(Sokoine University of Agriculture, 2014) Ashraf, Ashraf Mohamed
Onion (Allium cepa L.) yield in Kilosa is said to be very low compared to the world production of about 22 t ha’1. Poor crop husbandry including the use of unrecommended types and rates of fertilizers at incorrect time of application was found to be. among the discrepancies facing onion production in the area. The purpose of this study was to establish and recommend the best combination and rate of N and P fertilizer sources for onion under Kilosa agroecological conditions. A field trial was conducted at Malolo village between September 2012 - January 2013 (dry season) and February 2013 - July 2013 (wet season). The experiment was laid out in split plot design with three replications. Two onion varieties namely; Red Bombay and Red Creole were used and assigned to the main plots. N and P fertilizer sources, each at the rates of 0, 50 and 100 kg N ha'1 and 0, 40 and 50 kg P ha'1, respectively were assigned to the subplots. Data were collected on vegetative growth, yield and bulb quality. They were then subjected to analysis of variance using GENSTAT 14th Edition at a difference declared significance of 5% level. Results showed significant differences between varieties in growth, yield and quality components. Red Bombay performed better in productivity in both dry and wet seasons compared with Red Creole. Wet season promoted better productivity than the dry spell. There was significant differences in yield between N and P sources at varying rates during the dry season, but insignificant during the wet season. Fertilizer combination of TSP and CAN at 50 kg P ha'1 and 100 kg N ha'1 respectively, is recommended as best for better productivity of onion plants under the Kilosa agroecological conditions.
Effect of final moisture content, cooling time and paddy variety on milling quality of rice (Oryza sativa, L.)
(Pearl Research Journals, 2016) Furahisha, Kulwa; Chove, Lucy Mlipano; Chaula, Davis
The study was carried out to establish the effects of three factors -final moisture content (FMC), shade-cooling time (CT) and paddy variety on rice milling quality. Paddy was sun dried to final moisture contents ranging from 9.0 to 15.5% (on wet basis) and shade-cooled for 0, 6, 12, 18, and 24 h at ambient temperature (27.20 to 35.10 o C). Five paddy varieties, TXD 88, TXD 306, SUPA, IRRITA 1, and IRRITA 2 were studied. The milling tests were carried out using a laboratory rice mill. Latin square design with 5 replications (5x5 orders) was used. Physical properties and milling quality in terms of total rice yield (TRY), head rice yield (HRY) and whiteness index (WI) were analyzed. The physical properties differed significantly (P<0.05) among varieties. SUPA had good size, shape and chalkiness whereas TXD 88 had poor quality for all these parameters. IRRITA 1 and IRRITA 2 produced higher TRY compared to other tested varieties. TXD 88 had higher whiteness index but lower HRY compared to other tested varieties. Higher yields, which were significantly different for TRY and HRY (P<0.05) were obtained at moisture content between 9.0 to 12.5% for TRY, but between 10.5 to 14.0% for HRY
Effect of improved tomato cultivars on productivity and profitability in Morogoro region, Tanzania
(Journal of Animal &Plant Sciences, 2016) Msogoya, T. J.; Mamiro, D.
The objective of this study was to assess yield, revenue and profit from F1 hybrid tomato cultivars compared to farmers' preferred open pollinated local tomato cultivars grown in Tanzania. Seeds of local and F1 hybrid tomato varieties were sourced from local agro-dealers. The experiment was laid out in a randomized complete block design with four treatments (cv. Assila, Eden, Shanty and Oxyl Premium) and four controls consisting of local tomato cultivars (cv. Tengeru 97, Tanya, Cal-J and Riogrande). A treatment was replicated three times each with 12 plants. The seedlings were planted at a spacing of 60 cm x 60 cm in an open field at Sokoine University of Agriculture during the rainy and dry seasons. Data on total and marketable fruit yields were analyzed using Genstat statistical software version 15 and treatment means were separated based on Fisher’s unprotected LSD test at p< 0.05. Seed and production costs were computed based on real cost while revenues and net profits were estimated based on fruit marketable yield and retail prices of TSh. 700 and 1000 per kilogram (One USD = TSh. 2000). Results indicated that cv. Assila significantly (p = 0.002) produced higher total and marketable fruit yields than all local tomato cultivars during both the dry and rainy seasons. Moreover, cv. Eden significantly (p = 0.002) produced higher total and marketable fruit yields than all local cultivars during the dry season only while cv. Shanty produced higher marketable yields than all local cultivars during the rainy season only. The production costs of F1 hybrid tomato cultivars were higher than those of local tomato cultivars during both seasons. Tomato cv. Assila produced higher revenue and net profit than all local cultivars during both seasons while cv. Shanty produced higher revenue and net profit than all local tomato cultivars during the rainy season only. It is therefore recommended that farmers in Morogoro region should grow cv. Assila during both the rainy and dry seasons, and cv. Shanty during the rainy season only.
Effect of urea and cowpea residues on growth and yield of rice variety makassane in Zambezia, Mozambique
(Sokoine University of Agriculture, 2012) Dinheiro, Virgilio Agostinho Gabriel
A field experiment was conducted to assess the effectiveness of cowpea residues (CR), and combination of urea as source of nitrogen on growth and yield of rice variety Makassane. A randomized complete block design (RCBD) was used with six treatments and three replications. The six treatments were control plot, 0% urea + 100% CR, 25% urea + 75% CR, 50% urea + 50% CR, 75% urea + 25% CR and 100% urea + 0 % CR. Soil and organic material analysis revealed that the soil was deficient in N. Data recorded were number of tillers, plant height, leaf area, days to 50% flowering, 1000 grain weight, days to physiological maturity, total dry matter, panicles per plant, spikelets per panicle and grain yield. The recorded data were analyzed by the analysis of variance and stepwise multi-regression techniques. The result showed that sole cowpea residues, urea and different combinations of organic and inorganic fertilizers significantly produced comparable higher rice grain yields over the control plot. Overall, the study results indicated that combination of organic and inorganic source of nitrogen at the rate of 50% urea + 50% CR could be the best combination strategy in improving rice grain yield. Furthermore, it is concluded that cowpea residues instead of urea could be used as a source of nitrogen for improving rice production.
Effect of variety mixtures on cowpea vegetable leaf and seed yields in a traditional cowpea/maize intercropping system in the semi-arid tropics of Uganda
(Sokoine University of Agriculture, 2009) Okonya, Joshua S.
Cowpea is considered to be one of the top four leafy vegetables in Uganda grown for both its seed and leaves. Vegetable leaves are more popular than seed in the Eastern and Northern parts of the country and are a source of protein and micronutrients for the resource-poor subsistence farmers. Cowpea is usually grown in intercrop with maize, sorghum, cassava or mung bean but sole cropping is also practiced by several farmers. Most farmers in Soroti and Kumi districts continue to grow landraces (‘Ecirikukwai’ and ‘Ebelat’) because no improved varieties have been successfully bred/promoted. Erratic rainfall, low soil fertility and insect pests are among the most important constraints to cowpea production in Uganda leading to low seed yields (200-400 kg/ha) while leaf yield levels had never been assessed. Agronomic strategies to optimise both leaf and seed yields like through the use of variety mixtures are long overdue. Variety mixtures containing up to four cowpea varieties were grown in intercrop with maize during the first cropping season of 2008 at NaSARRI, Serere, Kikota village and Kogili village in Eastern Uganda. The results of these three experiments indicated that: accumulated dry matter leaf yield from 3-4 harvests and seed yield ranged from 34.7 to 70.9 kg/ha and 33.4 to 551.2 kg/ha, respectively. There was no significant difference between accumulated leaf yield of mixtures and the means of their respective component varieties. Though not significant, mixtures had both positive (4.3 to 111.4%) and negative (3 to 72.5%) effects on seed yield. Seed and leaf yield did not always increase with increasing number of component varieties in a mixture. The leaf-harvesting strategy employed by farmers enhanced seed yield in some but not all the treatments. Seed yield components like pod number, seeds/pod and 100- seed weight were not significantly affected by leaf-harvesting. On average, leaf yield was more stable in plots with mixtures than those with single cowpea varieties. Levels of leaf protein and iron ranged from 27.9 to 34.8% and 164.1 to 796.3 pg/g, respectively. Cowpea leaves were ranked first by farmers from the region among the top four leafy vegetables of spider-flower, amaranth and white cabbage.
Effects of cutting interval and nitrogen fertilizer rate on the yield and nutritive value of Brachiaria brizantha and Chloris gayana.
(Sokoine University of Agriculture, 1990) Mtengeti, Ephraim Joseph
The effects of three cutting intervals (20, 40 and 60 days ) and four levels of N application (0, 100, 200 and 400 kg N/ha) on the dry matter yield, dry matter content, tiller height, CP content, CP yield, N utilization efficiency, in vitro dry matter digestibility and in vitro digestible dry matter yield were studied in Chloris gayana and Brachiaria brizantha over a period of 120 days in 1987 in a field experiment at Sokoine University of Agriculture farm in Tanzania. The dry matter yield of the grasses increased with extension of the cutting interval up to 40 days and then declined thereafter. dry matter yield of the grasses increased with increasing N rate.The dry matter content increased with increasing cutting interval decreased with increasing N rate.The green leaf and stem dry matter yields increased with increasing N rate.Extended period between successive cuts slightly reduced green leaf dry matter yield and slightly increased the the stem dry matter yield. Leaf:stem ratio was not significant!;. ( P > 0.05) affected by extension of the cutting interval. Tiller height increased significantly (P < 0.01) with increasing N rate and cutting interval.The CP concent of the herbage decreased with extension of the cutting interval. The 'CP yield increased with increasing N rate and extension of the cutting interval to 40 days and declined thereafter.The recovery of applied N increased with increasing N rate up to 200 kg N/ha then declined thereafter.yield response in terms of kg DM Dry matter per kg of applied N decreased with increasing N rate.In vitro dry matter digestibility of the grasses increased with increasing N rate and decreased with extension of the cutting interval.Brachiaria brizantha had a significantly (P < 0.01) higher in vitro dry matter digestibility than Chloris gayana at all cutting intervals.The in vitro digestible dry matter yield of the grasses increased with nitrogen rate. It also increased with extension of the cutting interval up to 40 days and then declined thereafter. The results of this experiment support the view that, the productivity of grasses can be improved by N fertilization. In this study it has been shown that B. brizantha and C. gayana should be harvested every 40 days during the period of favourable growth in order to balance the productivity and the quality of the produced herbage.
Effects of rate and time of nitrogen application on growth, leaf nutrient contents and yield of sugarcane at Kilombero Sugar Estates
(Sokoine University of Agriculture, 1985) Mkelenda, Abdallah Salum
ABSTRACT A field study on the effects of rate and time of nitrogen fertilization on growth, leaf nutrient contents and yield of sugarcane (Saccharum officinarum) variety N. Co.376 was conducted at Kilombero Sugar Estates in Morogoro region during the 198?/83 cropping season*Four rates of N and three different times of application were tested in factorial combination in a randomized block design using a plantcane crop*The IT rates were 0, 100, 200 and 300 kg 10xa applied as ammonium sulphate * The times of application were (i) all the N applied at planting, (ii) all the N applied at three months, and (ill) N applied in two split doses: one half at planting, and the rest at three monthd* The crop was grown for twelve months.The germination, stalk population counts, and the heights of the plants were determined.The N, 2?, K, Ca and Mg nutrition of the crop were assessed by analysing cane leaves sampled from two—and four-montha old plants* The yield and quality of the crop were determined at harvest time.The germination was good and was not affected by the treatments* Nitrogen fertilization increased stalk population, and cane growth significantly. Nitrogen application increased the concentration of N in the leaves sampled at the two ages, For the two months samples the leaf N concentration ranged from 1.87% to 2.29%, while for the four months samples the concentration ranged from 1,38% to 1.94%. Leaf N concentrations in the four months old plants were highly correlated with sucrose contents in the plants,. cane yield, and sugar yield. suggesting that leaf IT concentration could be used in predicting these parameters. Using a curvelinear relationship between leaf IT concentration and sugar yield a tentative critical N concentration of 1,78% was established.The concentrations of P, K, Ca, and Mg were considered to be within the adequate range for the crop. All rates of IT increased cane yield significantly but sugar yield increased with increase in applied N only up to 100 kg N/ha, Further increase in N did not cause further increase in sugar yield:'mainly because of the negative effect of higher rates of N on sucrose accumulation in cane plants. In addition, nitrogen application reduced the quality of the juice; i.e. the brix, pol and juice purity.Time of application did not have any significant effect on any of these parameters.The results of the study suggest that the optimum rate of IT for sugar production in Ruaha area of Msolwa Estate is around 100 kg 10ia and that all the IT can be applied in the furrows at planting. Also leaf analysis technique can be used for assessing the sufficiency of IT in cane plants.
Evaluation of quality protein maize synthetic germplasm for drought tolerance
(Sokoine University of Agriculture, 2008) Bilaro, Atugonza Luta
Twenty one Open Pollinated Quality Protein Maize genotypes were evaluated fbr drought tolerance under three conditions of moisture regimes i.e. pre flowering stress, flowering moisture stress and optimal moisture to identify genotypes that maintained high yield under drought and well watered conditions. The experiment was conducted at Ilonga research station during rain free period of August to November, 2006, and Selian Arusha during rain season of 2006/07. Yield differences between moisture regimes were significantly (p < 0.001) different. Optimal moisture regime had the highest mean grain yield (1.49t/ha) followed by flowering stress (1.15t/ha) while pre flowering stress had the least mean grain yield (0.9t/ha). Correlation studies revealed that grain yield was related to number of days to anthesis, number of ears per plant, plant height, ear height, and leaf senescence. Of these, plant height, ear height, and number of ears per plant were consistently positively correlated with grain yield in all moisture regimes. Days to anthesis had varying correlations with grain yield depending on moisture conditions. Based on index values, entries 1 (EEQPMOPV-l-EA-#), 6 (EEQPM-13-EA半),10 (EEQPM- 34-EA-#), 13(EEQPM-45-EA-#), 14(EEQPM-49-EA-#), 19(POOL15QPM-SR-#-#) and 21 (Local check 1) performed better in most traits associated with drought. Grain yield, numbers of ears per plant, days to anthesis and leaf senescence were important selection criteria under drought but only grain yield and leaf senescence were important under both stress and optimal moisture conditions. Nine entries had above average yield and out of these only 3 i.e. 13(EEQPM-45-EA-#), 19 (POOL15QPM- SR-#-#) and 21 (Local Check 1) had stable performance across moisture regimes. Stable and high yielding genotypes should be evaluated under field conditions in the target environments so that farmers can select suitable genotypes to be proposed for release. Molecular characterization should be carried out to ascertain the degree of diversity available among the entries identified as best in different moisture regimes.
Evaluation of rice (oryza sativa £.) genotypes for adaptability to heat stress under controlled conditions in Morogoro
(Sokoine University of Agriculture, 2014) Vitta,Masanche Rajab
A study was conducted in the 2012/13 growing season, at Horticulture unit screen house and heat chamber at African Seed Health Centre in the Department of Crop Science and Production at Sokoine University of Agriculture. Morogoro. The aim of this study was to evaluate rice genotypes for adaptability to heat stress under controlled conditions in Morogoro, whereas, mutant rice genotypes originating from Kihogo red (Local variety), CG 14 (O.glaberrima), WAB 56-50 and WAB 56-104 {O. saliva) were evaluated. The results from screening of rice mutant lines which were subjected to heat stress at 45°C for different days of exposure showed variation in survival among genotypes tested. The survived rice seedlings were laid out as pot experiments in a completely randomized Design with three replications in the screen house. Data collected included plant survived from heat chamber, Days to 50% flowering, Tiller number per plant, panicle number per plant, plant height, panicle length, number of spikelets per plant, percentage sterility, 1000 grain weight, and grain yield per plant. Data were subjected to the analysis of variance (ANOVA). The results revealed that there were significant differences among the genotypes for all traits studied. In this study the effects of temperature were observed in plant height, Days to 50% flowering, panicle length, number of sp汰elets per panicle, 1000 grain weight, in almost all mutants whereas, grain yield of WAB 45-104 and 56-50 mutants were affected significantly. Also the following traits were favored by high temperature; Percent sterility, number of panicles per plant, number of tillers per plant and grain yield per plant for Kihogo red and CG 14. The phenotypic screen revealed the following mutants lines to be heat tolerant; KR 37, CG-14-7, CG 14-13,CG 14-16, WAB 56-104-36, WAB 56-104-43, WAB 56-104-82, WAB 56-104-40, WAB 56-104-12, WAB 56-104-123, WAB 56-104-181, WAB 56-50-82 and WAB 56-50-132. Therefore these lines could be grown in the area where temperature exceeded the normal range for rice cultivation.
Evaluation of rice (oryza sativa £.) genotypes for adaptability to heat stress under controlled conditions in Morogoro
(Sokoine University of Agriculture, 2014) Vitta, Masanche Rajab
A study was conducted in the 2012/13 growing season, at Horticulture unit screen house and heat chamber at African Seed Health Centre in the Department of Crop Science and Production at Sokoine University of Agriculture. Morogoro. The aim of this study was to evaluate rice genotypes for adaptability to heat stress under controlled conditions in Morogoro, whereas, mutant rice genotypes originating from Kihogo red (Local variety), CG 14 (O.glaberrima), WAB 56-50 and WAB 56-104 {O. saliva) were evaluated. The results from screening of rice mutant lines which were subjected to heat stress at 45°C for different days of exposure showed variation in survival among genotypes tested. The survived rice seedlings were laid out as pot experiments in a completely randomized Design with three replications in the screen house. Data collected included plant survived from heat chamber, Days to 50% flowering, Tiller number per plant, panicle number per plant, plant height, panicle length, number of spikelets per plant, percentage sterility, 1000 grain weight, and grain yield per plant. Data were subjected to the analysis of variance (ANOVA). The results revealed that there were significant differences among the genotypes for all traits studied. In this study the effects of temperature were observed in plant height, Days to 50% flowering, panicle length, number of sp汰elets per panicle, 1000 grain weight, in almost all mutants whereas, grain yield of WAB 45-104 and 56-50 mutants were affected significantly. Also the following traits were favored by high temperature; Percent sterility, number of panicles per plant, number of tillers per plant and grain yield per plant for Kihogo red and CG 14. The phenotypic screen revealed the following mutants lines to be heat tolerant; KR 37, CG-14-7, CG 14-13,CG 14-16, WAB 56-104-36, WAB 56-104-43, WAB 56-104-82, WAB 56-104-40, WAB 56-104-12, WAB 56-104-123, WAB 56-104-181, WAB 56-50-82 and WAB 56-50-132. Therefore these lines could be grown in the area where temperature exceeded the normal range for rice cultivation.
Facilitating International Agricultural Trade Through Science: the Case of Tephritid Flies
(Sokoine University of Agriculture, 2018) Prof. Maulid Walad Mwatawala
International agricultural trade is important in addressing spatial and temporal food shortages across the globe. Agricultural trade generates income and contributes to economies of many countries. Unfortunately, there are various risks associated with the movement of agricultural commodities across borders. The spread of pests across countries is one of the great risks. The International Plant Protection Convention (IPPC), which is an agreement between nations, aims at preventing and controlling the introduction and spread of pests of plants and plant products across national boundaries. IPPC formulates various standards and guidelines that can be adopted by member states to formulate municipal phytosanitary laws against the introduction of pests. Countries normally conduct Pest Risk Analysis (PRA) in order to facilitate agricultural trade. This process requires scientific evidence on the identity and occurrences of pests in an area and a possible entry and the establishment and the spread of those pests into exotic places. Fruits and vegetable trade is important for food and security among the global population. However, fruit trade introduces the risk of the spread of pests, including fruit flies. Most fruit flies cause heavy losses to the fruit industry and these are therefore of quarantine importance. Research which has been conducted across the globe provided scientific evidence on the possible spread of fruit flies in order to facilitate trade. The Sokoine University of Agriculture (SUA) collaborated with various partners in the world to generate important information that is a prerequisite for conducting PRA. This inaugural lecture highlights key findings that include identification of new species, resolution of cryptic species, host range and preference, spatial and temporal distribution, and mitigation options against the selected economically important fruit flies.
Fatty acid profiles and lipid oxidation status of sun dried, deep fried, and smoked sardine (Rastrineobola argentea) from Lake Victoria, Tanzania
(Taylor & Francis, 2019) Chaula, Davis; Laswai, Henry; Chove, Bernard; Dalsgaard, Anders; Mdegela, Robinson; Hyldig, Grethe
Freshwater fishes contain long chain omega-3 and omega-6 polyunsaturated fatty acids (PUFAs) of highest nutritional value. PUFAs in fish are susceptible to oxidative damage during processing and subsequent storage. Sardines (Rastrineobola argentea) are an important fish species of Lake Victoria, constitut- ing 72.3% of the total landings by weight on the Tanzanian side of the lake. Fatty acid profiles and lipid oxidation status of sun-dried, deep-fried, and smoked sardines were investigated. Lipid oxidation was assessed by peroxide value, thiobarbituric acid reactive substances (TBARS), and free fatty acids. Fatty acids were analyzed by gas chromatography with flame ionization detector. The three omega-3 PUFAs: docosahexaenoic acid (C22:6n-3), docosapentaenoic acid (C22:5n-3), and eicosapentaenoic acid (C20: 5n-3) contributed 57–60, 63, and 38% of PUFAs in sun-dried, smoked, and deep-fried sardines, respectively. Lipid oxidation reactions were more pronounced in sardines dried on sand and rocks, with TBARS values 97.87 and 84.18 μmolMDA/kg, respectively. The polyene index was significantly lower (p < 0.05) in deep-fried sardines, indicating lower retention of PUFAs in the product. Lake Victoria sardines are a rich source of omega-3 PUFAs. PUFAs in sun-dried sardines are prone to oxidative damage. Smoking resulted in relatively higher retention of omega-3 fatty acids in products.
Fungi intercepted in seeds of pigeon pea ( (cajanus cajan (l.) grown in Northern Tanzania and relation to quality attributes of the seeds
(International Research Journal of Biological Sciences, 2019) Tarmo, Theophili; Msuya, Dunstan; Njau, Paul
Fungi associated with Pigeon pea seed were studied using 80 seeds samples of pigeon pea collected from Babati and Karatu districts in northern Tanzania. The standard moist blotter test was used to detect fungi on seeds. The tested pigeon pea samples yielded d more than 12 different fungal species. Fusarium udum which is a pathogen of seed health certification significance was detected in 33 samples from Babati (equivalent to 82.5%) and 36 samples from Karatu districts (equivalent to 90%) of the samples. Eleven n other seed infesting fungi were also intercepted, with Rhizopus spp appearing in all samples and having the highest incidence of 23.2% for Karatu and 16.1% for Babati district followed by Aspergillus flavus having the incidence of 20.3% and 15.7% for Karatu atu and Babati districts, respectively. The other species ranged between 1.1% and 10.1% for Babati and 0.7% and 13.7% for Karatu. Significant correlation existed between seed purity and incidence of Cladosporium spp and between seed moisture content and in incidence cidence of Fusarium moniliforme; but the correlation with purity was positive against expectation. Even though farm farm-saved saved seeds may be localized with the practicing farmer or within a restricted locality, generally it is suggested that in those areas where seed borne pathogens are endemic and farm-saved farm seeds is predominant farmers’ awareness on Fusarium wilt disease should be created. It is also suggested that farmers should be trained on how to reduce seed transmission of the diseases at least by rouging the infected plants in the field and selective harvesting of the crop to be used as seed.

Browse

Browsing Crop Science and Production Collection by Title