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101.
Proteins, inevitable for nutritional security of human beings and legumes, by far, are the cheapest source of this vital nutrient. The escalating prices and never halting population growth limit the per capita availability of protein-rich legumes. In view of limited land resource and need to grow other food crops, the greater protein harvests are possible only by increasing the protein levels of popularly grown legumes. In this context, attempts were made for raising the protein content in pigeonpea [Cajanus cajan (L.) Millsp.] through traditional plant breeding tools. For this, the high-protein trait was successfully transferred from wild relatives of pigeonpea to the cultivated types. In the derived inbred lines, the protein content was significantly enhanced from 20% - 22% to 28% - 30%. Two high-protein lines HPL 40 and HPL 8 also produced 2100 and 1660 kg/ha grain yield, respectively. This simply means that, in comparison with traditional cultivars, the cultivation of high-protein lines will provide additional 100 kg/ha of digestible protein to the farming family. This paper, besides describing the breeding procedures, also discusses the accomplishments of this breeding endeavour with respect to its various nutritional and biological properties.  相似文献   
102.
Long duration required for generation advancement in pigeonpea [Cajanus cajan (L.) Millsp] is one of the major bottlenecks in realizing rapid genetic gains. Therefore, a technology for rapid generation turnover is warranted to facilitate the development of new cultivars and recombinant inbred lines. Breeding of early‐maturing cultivars has now opened up the possibility of rapid generation advance (RGA) in this crop. This paper reports the development of an RGA technology that integrates the germination of immature seeds with single seed descent method of breeding. The results showed that immature 35‐day‐old seeds can be used successfully to turn over a generation of pigeonpea with 100% seed germination. These way 3/4 successive generations can be grown within a year. The methodology presented in this study will accelerate the breeding process for breeding cultivars and develop rapidly the materials required for genomics research in pigeonpea.  相似文献   
103.
Five short-duration pigeonpea (Cajanus cajan (L.) Millsp.) genotypes were grown at three plant populations in three locations during the 1986 and 1988 rainy seasons, to determine the physiological basis of observed variations in yield. Significant differences were found in seed yield (Y), crop growth rate (C), and the durations of vegetative (Dv) and reproductive (Dr) growth, and partitioning (P). These were attributable to genotypes and their interactions with environments (except for C). Variation in C, Dr, and P together explained 78 % of the observed variation in Y due to different genotypes and environments. Crop growth rate alone contributed about 71 % of the variation in Y, and reached an optimum value of around 6.5 kg ha?1°Cd?1. Crop growth rates increased with the duration of the vegetative period and with plant population. However, a negative relationship between C and P resulted in plant population having little effect on seed yield. The maximum-yielding genotype, ICPH 8 had the highest C and an intermediate P.  相似文献   
104.
Ochrus chickling ( Lathyrus ochrus (L.) D.C.) is a promising feed legume for rain-fed farming systems in the Mediterranean environments of West Asia and North Africa (WANA) because of its drought tolerance and resistance to broom rape ( Orobanche crenata Forsk.). However, it is highly susceptible to cold and improving Its resistance would further improve its adaptation.
The potential of the chlorophyll fluorescence technique in screening for frost sensitivity in seedlings of five Lathyrus ochrus genotypes and one each of Vicia ervilia (L.) Wild and V. sativa L. was assessed by measuring the rate of rise in induced or variable chlorophyll fluorescence of fully developed leaflets after cold hardening in the open and subsequent exposure to freezing. The method differentiated the highly frost-susceptible L. ochrus genotypes from the more tolerant Vicia species. Testing the technique with nine genotypes of L. ochrus in which the plants were established, cold-hardened and frost-stressed under controlled conditions confirmed its sensitivity even to reveal the narrow inter plant differences that generally exist within a cultivar or genotype to frost. It is therefore considered as a useful screening technique for cold/frost tolerance in L. ochrus.  相似文献   
105.
106.

Nutritional scarcity during summer and winter is a major constraint for sheep rearing in the semi-arid tropical region. In this region, a new crossbred sheep has been developed by the crossing of a native sheep breed Malpura with a breed of hot-humid coastal region breed Garole. A study was conducted for 9 weeks to assess the physiological response of crossbred (Garole x Malpura x Malpura, GMM) rams under nutritional scarcity in the semi-arid tropical region. Eighteen adult crossbred rams were randomly allocated into three groups of six animals each. The groups are G1 (control, ad libitum feeding), G2 (20% less than ad libitum feeding), and G3 (30% less than ad libitum feeding). The animals were stall-fed with a diet consisting of 70% roughage (Cenchrus ciliaris hay) and 30% concentrate feed. Body weight gain, average daily gain, and feed intake were significantly (P?<?0.05) lower in G2 and G3 as compared to G1 rams. Water intake was significantly (P?<?0.05) higher in G2 and G3. Physiological responses, blood biochemical and endocrine profile did not differ between the groups. The results indicate that the crossbred rams evolved through the crossing of the hot semi-arid tropical region breed with hot humid coastal region breed are able to maintain their body homeostasis despite nutritional scarcity although their body weight decreased.

  相似文献   
107.

The effect of rumen-protected nutrients (bypass fat, BPF; bypass protein, BPP; or their combination, BPPF) was investigated in Murrah buffaloes during the early stage of lactation. Forty Murrah buffaloes (BW 531.92?±?10.85 kg) just after parturition were randomly distributed into four groups according to parity and milk production. Buffaloes individually fed ration from day 0 to 90 postpartum according to feeding group and nutrient requirement. Control and BPF fed groups received a concentrate mixture, CM1 with 25% rumen-protected protein (using barley, wheat bran, and mustard oil cake), BPP and BPPF groups received a second concentrate mixture, CM2 with 40% rumen-protected protein (using barley, de-oiled rice bran, and cottonseed cake). Bypass fat fed groups (BPF and BPPF) additionally were supplemented with 15 g BPF (Ca salt of long-chain fatty acids) per kg milk yield in their respective concentrate mixtures. Dry matter intake, body weights, body condition score, and total milk yield were similar between groups (P?>?0.05). Fat-corrected milk (FCM) production was improved (14.5%, P?>?0.05) in groups fed BPP and BPPF, while significant (19.45%, P?<?0.05) improvement was observed in BPF-fed group. Overall mean values of milk fat, solid not fat, protein, lactose, and total solids were found to be high (P?<?0.05) in treatment groups as compared with control values. It may be concluded that supplementation with BPP or BPF either alone or in combination positively influences the quality of milk produced in Murrah buffaloes during early lactation and BPF additionally had improvement on the quantitative trait of milk as well.

  相似文献   
108.
  1. A total of 32 Lactobacillus isolates, 8 each from the crop (LGFCP1–LGFCP8), proventriculus (LGFP9–LGFP16), ileum (LGFI17–LGFI24) and caeca (LGFCM25–LGFCM32) were isolated from 25 adult guinea fowl (Pearl variety), 22–28 weeks of age, and characterised morphologically, physiologically, biochemically and by molecular methods.

  2. Isolates were screened for their probiotic quality using range of in vitro tests: aggregation test, cell surface hydrophobicity, resistance to bile salts and acidic conditions, enzymatic tests and coaggregation and antagonistic test.

  3. Based on in vitro test results and a novel scoring method, the two best isolates were selected and partial 16S rRNA sequencing was done. BLAST (Basic Local Alignment Search Tool) analysis of sequence of isolate LGFCP4 showed 99% genetic identity with Lactobacillus plantarum and LGFP16 with Lactobacillus reuteri.

  4. The study shows that these two microbial agents may be suitable as potential probiotic candidates in guinea fowl, as well as in a feed supplement for other poultry species.

  相似文献   
109.
Several randomly selected glasshouse grown somaclones of rose scented geranium, Pelargonium graveolens L’Her Ex Ait. cv. Hemanti were successfully transferred to the field in Northern India for evaluation. Two distinct morphotypes were described on the basis of leaf dentation-one resembling the parental cultivar in having highly dentated leaves (HDL) and the other with less dentated leaves (LDL). After repeated field-testing for 3 consecutive years, the HDL clones closely resembled the parental cultivar with respect to the different quantity and quality determining traits, while the LDL group was clearly different. The field established LDL somaclones possessed higher herb yield, number of branches and other oil yield attributing traits as compared to the HDL clones and the parent cultivar. The chemical investigations of the essential oil revealed significant differences between the LDL clones, the HDL clones and the control. Selection of such somaclones, which are superior to the parental in most of the quantitative and qualitative traits and show better adaptability to different areas of cultivation, will help towards commercialization of geranium in India.  相似文献   
110.
In this study, inoculation of the chickpea (Cicer arietinum) with the novel symbiotic fungus (Piriformospora indica) was analysed in combination with the Tn5-lacZ-tagged phosphate-solubilising bacterium Pseudomonas striata. This study aims to evaluate whether the co-inoculation of these two species would enhance the population buildup of P. striata in the rhizosphere, P uptake, growth and yield of chickpea. Single inoculation of P. indica and P. striata has a negative effect on plant growth and yield of chickpea. Data showed that the combination of the two microorganisms had a synergistic effect on population buildup of P. striata and plant dry biomass with respect to their single inoculation. However, the P uptake was not significantly influenced by single or combined inoculation of two species. At 20 days after sowing, the influence of combined inoculation on the population of P. striata was positive; at 60 days after sowing, it was neutral as the populations in treatments with single and combined inoculation were at par; and at harvest, it was negative The population of P. striata was higher at flowering stage as compared to 20 days after sowing and at harvest.  相似文献   
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