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921.
922.
After an initial survey on feeds and feeding practices at Kumaon Himalaya, the potential of oak leaves feeding was evaluated in six native heifers (Bos indicus; 101.5?kg BW, 18?C24?months) in a partial switch-over design involving two animals each on each treatment at a time. The feeding treatments involved high and low levels of oak leaves (Quercus leucotrichophora, oak leaves (OL)) supplemented to local mixed grass hay (GH) which were GH (G1), GH + low level (42.5?%) of OL (G2) and GH + high level (63.6?%) of OL (G3). The feeding trial for each treatment was conducted for 40?days that ended with a digestibility trial of 6-day duration. The dry matter (DM) intake (kg/day) was non-significantly higher in G3 (3.52) than G2 (3.11) and G1 (2.96). Intake of crude protein (CP) (g/day) was significantly (P?<?0.001) higher in both G2 and G3 than G1. The digestibility of DM, CP, organic matter, ether extract and total carbohydrates increased (P?<?0.001) linearly in OL-fed groups as compared to control. The total digestible nutrients (TDN) (kg/day) intake was significantly higher (P?<?0.05) in G3 compared to G1, but it was comparable between G1 and G2. Intake of DM, CP, digestible CP (DCP) and TDN/metabolizable energy (ME) per kilogram metabolic body weight was significantly higher (P?<?0.01) in G3 than G2 which in turn was also higher (P?<?0.01) than G1. The animals under G1 had negative gain (?50?g/day) compared to 146 and 306?g/day in G2 and G3, respectively. Feeding of OL reduced serum urea and creatinine level and supported serum protein concentration better in G3 compared to G2. The feeding of cattle on GH alone was lacking in both energy and protein for sustaining minimum levels of production, whereas in combination with OL at 36.4:63.6 ratios supported minimum level of production (ADG 300?g) with near nutritional adequacy for major nutrients (CP, DCP, TDN, ME) but with a caution for the minor nutrients like calcium and phosphorus that need to be supplemented. 相似文献
923.
Jérôme Bernier Arvind Kumar Ramaiah Venuprasad Dean Spaner Satish Verulkar Nimai P. Mandal Pramod K. Sinha Puvvada Peeraju Praba R. Dongre R. N. Mahto Gary Atlin 《Euphytica》2009,166(2):207-217
A large-effect QTL for grain yield under drought conditions (qtl12.1) was reported in a rice mapping population derived from Vandana and Way Rarem. Here, we measured the effect of qtl12.1 on grain yield and associated traits in 21 field trials: ten at IRRI in the Philippines and 11 in the target environment
of eastern India. The relative effect of the QTL on grain yield increased with increasing intensity of drought stress, from
having no effect under well-watered conditions to having an additive effect of more than 40% of the trial mean in the most
severe stress treatments. The QTL improved grain yield in nine out of ten direct-seeded upland trials where drought stress
was severe or moderate, but no effect was measured under well-watered aerobic conditions or under transplanted lowland conditions.
These trials confirm that qtl12.1 has a large and consistent effect on grain yield under upland drought stress conditions, in a wide range of environments. 相似文献
924.
A set of 45 diverse Asian and African origin/bred populations of pearl millet were investigated multi-locationally for morphological traits including grain yield and assessed for their fertility restoration ability on three cytoplasmic male sterility(CMS) systems in two contrasting seasons. Significant genetic variation was found for all the yield linked traits. Multivariate analysis for grain yield and its component traits grouped these populations into five clusters. Most of the Asian origin populations grouped into single cluster(Cluster III) and separated from the rest of the African origin populations indicating the presence of correspondence between clustering pattern and geographical origin of the populations. Clusters dominated with Asian populations(As-As) had linkages with early flowering, short plant height, more number of tillers, small and thin panicles, small seeded and low grain yield compared to the clusters dominated by African populations(Af-Af) or African origin and Asian bred(Af-As) populations.Genetically related populations having common parentage were found grouped in same clusters.Fertility restoration/maintainer frequency of 45 populations on three diverse CMS systems revealed that overall fertility restoration frequency was highest for A1(86%) followed by A4(37%) and for A5(7%) CMS system. Five populations were identified as potential sources for developing maintainer lines for all three CMS systems and eight populations were identified specifically for A;and A;CMS systems. A set of 11 and four populations were identified for restorer line development exclusively for A;and A;CMS system,respectively. Six populations were identified for the development of dual restorers for both A;and A;CMS system. 相似文献
925.
Singh K Rani A Kumar S Sood P Mahajan M Yadav SK Singh B Ahuja PS 《Tree physiology》2008,28(9):1349-1356
Tea (Camellia sinensis (L.) O. Kuntze) leaves are a major source of flavonoids that mainly belong to the flavan 3-ols or catechins. Apart from being responsible for tea quality, these compounds have medicinal properties. Flavanone 3-hydroxylase (F3H) is an abundant enzyme in tea leaves that catalyzes the stereospecific hydroxylation of (2S)-naringenin to form (2R,3R)-dihydrokaempferol. We report a full-length cDNA sequence of F3H from tea (CsF3H Accession no. AY641730). CsF3H comprised 1365 bp with an open reading frame of 1107 nt (from 43 to 1149) encoding a polypeptide of 368 amino acids. Expression of CsF3H in an expression vector in Escherichia coli yielded a functional protein with a specific activity of 32 nmol min(-1) mg protein(-1). There was a positive correlation between the concentration of catechins and CsF3H expression in leaves of different developmental stages. CsF3H expression was down-regulated in response to drought, abscisic acid and gibberellic acid treatment, but up-regulated in response to wounding. The concentration of catechins paralleled the expression data. Exposure of tea shoots to 50-100 microM catechins led to down-regulation of CsF3H expression suggesting substrate mediated feedback regulation of the gene. The strong correlation between the concentration of catechins and CsF3H expression indicates a critical role of F3H in catechin biosynthesis. 相似文献
926.
927.
喜马拉雅山西侧山岭森林的生物量密度、利用和生产动态(英文) 总被引:1,自引:0,他引:1
证据显示印度喜马偕尔北部的喜马拉雅州森林生物量大量减少。政府通过局部测定核查了森林生物量减少情况。本文以树木生物量来衡量森林退化,评估了主要用地类型内森林生物量的现状,检查了森林可持续性。结果表明,保育林分树木地上部最大生物量平均为1158t·hm-2,保护林、休耕地、耕作非灌溉地、草地、果园和耕地灌溉地的平均生物量依次是728,13,11,8,5和3t·hm-2。当地农民用于烧柴、马料或其他用途的树木生物量仅占可获得的生物总量的0.31%。现在的取用水平只能在短期内维持森林可持续性,从长期来看森林再生不足。采用对数生长模型对未来30年的森林生物量进行料模拟,并通过敏感性分析对影响系统行为的输入变量的相对显著性进行了分析。拟合模型强调了未来的森林资源降低不可避免。政府部门应该积极响应,出台相应政策才能有效地保护森林资源。 相似文献
928.
In this paper multi-objective differential evolution (MODE) approach is proposed for the simultaneous evolution of optimal
cropping pattern and operation policies for a multi-crop irrigation reservoir system. In general, farming community wants
to maximize total net benefits by irrigating high economic value crops over larger area, which may also include water-intensive
crops and longer duration crops. This poses a serious problem under water-scarce conditions and often results in crop failure.
Under varying hydrological conditions, the fixed cropping pattern with conventional operating rule curve policies may not
yield economically good results. To provide flexible policies, a nonlinear multi-objective optimization model is formulated.
To achieve robust performance by handling interdependent relationships among the decision variables of the model, the recent
MODE technique is adopted to solve the multi-objective problem. The developed model is applied for ten-daily reservoir operation
to a case study in India. The model results suggest that changes in the hydrologic conditions over a season have considerable
impact on the cropping pattern and net benefits from the irrigation system. Towards this purpose, the proposed MODE model
can be used to evolve different strategies for irrigation planning and reservoir operation policies, and to select the best
possible solution appropriate to the forecasted hydrologic condition. 相似文献
929.
The Upland Settlement Project of Bangladesh as a Means of Reducing Land Degradation and Improving Rural Livelihoods 总被引:1,自引:1,他引:0
Because of illegal logging, increased population pressure and intensified shifting cultivation, forest coverage of the Chittagong
Hill Tracts (CHT) has decreased drastically resulting in land degradation. Many development projects have been implemented
to combat forest loss and land degradation and also to improve the livelihoods of the hill people. This paper reports an empirical
study of the Upland Settlement Project (USP) of Bangladesh which was undertaken to prevent land degradation and enhance the
standard of living of the people. Planters were found to have given up shifting cultivation and adopted soil conserving agroforestry
practices, and forest coverage has been increased in the project village. Interacting with project staff members, government
officials and NGOs assisted planters in diversifying livelihood strategies thereby reducing dependency on project resources.
Rich planters, utilizing their own capacity, expanded their income sources successfully. Poor planters still remain wage labourers
because they do not have sufficient finance and networks to invest in productive ventures. Planters’ participation in project
activities and the information flow between them and project staff were found to be minimal. Suggestions are made for the
continuity of project functions, which involve greater participation of planters in rubber management functions, improved
information flow, resolution of land tenure and greater equality in distribution of rubber revenue.
相似文献
Tapan Kumar NathEmail: |
930.
Test‐crosses for estimating combining ability in potato although useful are difficult to make being labour intensive and time consuming, and due to the problem of sterility. The objective of the present study was to test methods for estimating general combining ability (GCA) of parents based on fewer matings. The GCA of 12 females estimated based on matings with specific single testers (top‐cross) and three types of bulk pollen (poly‐cross) were compared with those estimated by 72 (12 × 6) test‐crosses, using common testers in three types of matings. The study was conducted for 2 years at each of the two locations representing short‐days subtropical conditions in plains and long‐days temperate conditions in hills of India. Analysis of variance of test‐crosses showed that both general and specific combining ability effects were important for tuber yield, late blight resistance as well as general impression, the characters studied. Correlation coefficients among three types of matings showed that bulk pollen matings had poor effectiveness in predicting the GCA of the females, whereas matings with selected individual testers resulted in GCA estimates similar to those based on six testers. Thus use of top‐cross involving selected tester could substantially reduce the number of matings required for estimating the GCA. Among the six testers used, the tester CFK69.1 could estimate the GCA of the females with reasonably high accuracy both for tuber yield and general impression, and ‘Tobique’ for reaction to late blight. 相似文献