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51.
1. Three experiments were conducted to determine the apparent metabolisable energy, apparent digestible amino acid values, and utilisation of three maize varities in chickens: quality protein maize (QPM), hybrid maize Nityashree (HMN) and normal maize (NM).

2. There was no significant difference in the apparent metabolisable energy (AME) content amongst the three varieties of maize.

3. Lysine and threonine digestibilities were significantly higher in QPM compared to either HMN or NM. No difference in the digestibilities of other amino acids occurred among the three different maize varieties.

4. There was no difference between diets containing NM or HMN for body weight gain (21 and 40?d of age) and overall feed conversion ratio (0–40?d), but values were significantly higher for QPM (and Lys-supplemented NM) diets. The relative weights of dressed meat yield and giblets were unaffected by dietary replacement of NM with QPM, HMN, or Lys supplementation of the NM diet. However, abdominal fat content decreased and breast meat yield increased with both dietary replacement of NM with QPM and Lys supplementation of the NM diet.

5. The concentration of protein in serum was significantly increased by dietary replacement of NM with QPM. Adding Lys to the NM based diet significantly increased the Ca concentration in serum compared with NM or HMN diets. However, the highest concentration of Ca in serum was found in the QPM diet. The concentration of total cholesterol in serum significantly decreased by either replacing NM with QPM or adding Lys to the NM based diet, compared with the NM diet.

6. These results suggested that the feeding value of quality protein maize was superior to normal maize, while the feeding value of hybrid maize Nityashree was similar to that of normal maize.  相似文献   

52.
53.
Induced systemic resistance (ISR) is a mechanism by which certain plant beneficial rhizobacteria and fungi produce immunity, which can stimulate crop growth and resilience against various phytopathogens, insects, and parasites. These beneficial rhizobacteria and fungi improve plant performance by regulating hormone signaling, including salicylic acid (SA), jasmonic acid (JA), prosystemin, pathogenesis-related gene 1, and ethylene (ET) pathways,which activate the gene expression of ISR, the synth...  相似文献   
54.
Soil contamination by heavy metals negatively affects crop productivity, besides representing serious threat to human health. Grafting tomato onto appropriate rootstocks may raise Ni tolerance through limiting heavy metal uptake by roots and/or its translocation to the shoot and by detoxification. A greenhouse experiment was conducted to determine the influence of long‐term Ni exposure (0, 25, or 50 µM) on crop productivity, fruit quality, leaf chlorophyll content, fluorescence, electrolyte leakage, catalase (CAT), ascorbate peroxidase (APX), and guaiacol peroxidase (GPX) activities in leaf, proline content, membrane lipid peroxidation, and mineral composition of tomato plants cv. Ikram, either self‐grafted or grafted onto three rootstocks: Black Beauty, Unifort, and Maxifort. Significant reduction in yield was observed in response to an increase in Ni concentration with more detrimental effects at 50 µM Ni. The fruit dry matter and total soluble solids content increased under severe Ni stress. The depression of crop performance under Ni toxicity was attributed to a decrease in leaf pigments (SPAD index), efficiency of PSII, macro‐ and microelements, and increase in lipid peroxidation and membrane damage. Plants grafted onto tomato rootstocks Maxifort and Unifort exhibited higher chlorophyll content, photochemical activity of PSII, antioxidant activity of APX and GPX, lower accumulation of MDA, and a better nutritional status (higher Ca and Fe, and lower Ni) in the leaf tissues in comparison with self‐grafted plants and those grafted onto Black Beauty. Plants grafted onto tomato rootstocks Unifort and especially Maxifort could minimize the nickel toxicity by improving nutritional status and detoxification processes.  相似文献   
55.
Leafy vegetables are highly perishable and their shelf life depends on duration and conditions of storage. A low cost storage structure was used to extend the shelf life of amaranth and fenugreek and their quality was evaluated on the basis of retention of -carotene, ascorbic acid and chlorophyll during storage. Losses of -carotene ranged from 46.5 to 85.0% for amaranth and 24.0 to 73.0% for fenugreek depending on duration and conditions of storage. Similarly ascorbic acid retention varied from 9–32% for amaranth and 23–80% for fenugreek. Results showed that the degradation of quality parameters was faster at ambient conditions and packaging of leaves in low density polyethylene bags was beneficial in improving shelf life and nutritive value. Low cost storage structure was similar to low temperature storage for retention of -carotene, ascorbic acid, chlorophyll content and enhancement of shelf life.  相似文献   
56.
Influence of eight common Indian spices on the protein quality of sorghum and chickpea was studied. Spices used include red chillies (Capsicum annum), black pepper (piper nigrum), coriander seeds (Coriandrum sativum) cumin seeds (Cuminum cyminum), garlic (Allium sativum), asafoetida (Ferula foetida), dry ginger (Zingiber officinale) and ajowan (Carum copticum). Addition of spices did not affect protein digestibility (TD) of sorghum. The BV of all sorghum diets with spices was higher than that of control diet. However, it was significant only in case of diets combined with red chilli + coriander (11) mix, black pepper + cumin (11) mix, coriander and cumin. Addition of spices did not have any effect on TD or BV of chickpea diets.  相似文献   
57.
58.
ABSTRACT

In India, inland aquaculture has emerged as a fast-growing enterprise and a viable alternative to the declining capture fisheries. The present paper is an attempt to assess Indian inland aquaculture with respect to its resource base, output trends, systems and activities, yield gaps, adoption and impact on aquaculturists, economics, returns to inputs, investment needs, and future prospects. The paper is largely based on existing literature and observations made as part of an ICAR-WorldFish demand supply project. Indian aquaculture is primarily limited to inland sector and carp-oriented; for that reason, this activity received special attention. Freshwater aquaculture observed tremendous growth in the past 15 years, but immense scope still exists for horizontal expansion and increases in productivity (vertical expansion). This is evidenced by the fact that the average farm fish yield is only one-third of that achieved in farm trials. The difference was mainly due to much higher input use in on-farm trials. Most of the aquaculturists were practicing extensive aquaculture, but aquaculturists with semi-intensive operations benefited most from adoption of technology. The benefit:cost ratios for different systems of aquaculture varied between 1.22 to 1.86. The return to capital was much higher than the return to labor, due to the low labor input. The semi-intensive aquaculture system would receive the greatest return from projected macrolevel investments, followed by extensive and intensive systems. Dedicated efforts are needed to meet the demand for quality fish seed and feed in order to achieve the desired 45% increase in area and greater than 50% increase in productivity. Based on the observations, activities designed to foster inland aquacultural development in India are recommended.  相似文献   
59.
We investigated mass mortalities of koi, Cyprinus carpio Linnaeus, 1758, experienced in South Indian fish farms by virus isolation, electron microscopy, PCR detection, sequencing of capsid protein gene and transmission studies. Samples of moribund koi brought to the laboratory suffered continuous mortality exhibiting swimming abnormalities, intermittent surfacing and skin darkening. Irido-like virus was isolated from the infected fish in the indigenous snakehead kidney cell line (SNKD2a). Icosahedral virus particles of 100 to 120 nm were observed in the infected cell cultures, budding from the cell membrane. Virus transmission and pathogenicity studies revealed that horizontal transmission occurred associated with mortality. PCR analysis of infected fish and cell cultures confirmed the presence of Ranavirus capsid protein sequences. Sequence analysis of the major capsid protein gene showed an identity of 99.9% to that of largemouth bass virus isolated from North America. Detection and successful isolation of this viral agent becomes the first record of isolation of a virus resembling Santee–Cooper Ranavirus from a koi and from India. We propose the name koi ranavirus to this agent.  相似文献   
60.
There is an increasing recognition of the contribution of forests to food security of poor and marginalized people. However, empirical findings remain limited on how forests contribute to food security. Drawing on four case studies of community forestry in Nepal, this paper discusses pathways through which forests are contributing to food security needs of local communities. The evidence presented here was gathered through 4 years of action research and draws insights from the past 40 years of Nepal’s community forestry practice, which is often regarded as a successful case of conservation and development. It is shown that there are four distinct pathways through which community forests contribute to food security as a source of: (1) income and employment; (2) inputs to increase food production; (3) directly for food; and (4) renewable energy for cooking. Despite emerging pathways linking forest management to food systems at the local level, forestry policies and institutions have neither explicitly recognized nor strengthened the linkage between forest and food security. The paper highlights that there is a need for a fundamental shift in thinking from the conventional notion of ‘forests for soil conservation’ to ‘sustainable forest management for food security’.  相似文献   
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