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51.
Twenty three cultivars of carrot (Daucus carota L.) roots consisting of fifteen local and eight exotic cultivars were analysed for various chemical constituents including dry matter, total soluble solids (TSS), -carotene, total and reducing sugars, phenolics, phosphorus, zinc, manganese, copper, iron, sodium potassium and ash. In addition other characteristics such as days to maturity, root weight and length, flesh thickness, core diameter, number of forked and cracked roots per plot have been studied. Yellow carrots were found to have maximum root length, water soluble carbohydrates and minimum -carotene content. The exotic cultivars were found to have higher TSS content than the local cultivars, while the latter cultivars had higher mineral contents than the former. However, on the average, dry matter content, total water soluble sugars, reducing and non-reducing sugars were found to be greater in exotic cultivars than in local ones, but -carotene, phenols and phosphorus contents were greater in local cultivars. A significant positive correlation between -carotene content, ash percentage and days to maturity was observed. A wide variation in chemical constituents and plant characteristics was observed indicating a high genetic variability in the material under study.  相似文献   
52.
Composite flours prepared from wheat, greengram, bengalgram and blackgram flours were studied for the preparation of biscuits. Protein content of biscuits increased as the level of the pulse flours increased. Wheat flour containing bengalgram and blackgram flours adversely affected the top grain, texture and colour of biscuits. Biscuits made with higher levels of bengalgram (more than 15%) were tough and difficult to break and required higher compression force. Addition of greengram flour did not significantly affect top grain, texture and colour of biscuits. The biscuits made from 15% greengram supplemented wheat flour scored the highest for flavour characteristics. Thickness, diameter and spread ratio of biscuits containing different levels of pulse flours were significantly different from control sample. Sensory evaluation scores showed that acceptable biscuits can be prepared from wheat flour supplemented with these pulse flours at a level of 15 percent.  相似文献   
53.
Abstract

Tree clearing is a topical issue the world over. In Queensland, the high rates of clearing in the past were mainly to increase pasture production. The present research evaluates the impact of clearing on some soil biological properties, i.e. total soil respiration, root respiration, microbial respiration, and microbial biomass (C and N), and the response of soil respiration to change in temperature.

In-field and laboratory (polyhouse) experiments were undertaken. For in-field studies, paired cleared and uncleared pasture plots were selected to represent three major tree communities of the region, i.e. Eucalyptus populnea, E. melanophloia, and Acacia harpophylla. The cleared sites were chosen to represent three different time-since-clearing durations (5, 11–13, and 33 years; n=18 for cleared and uncleared plots) to determine the temporal impact of clearing on soil biological properties. Experiments were conducted in the polyhouse to study in detail the response of soil respiration to changes in soil temperature and soil moisture, and to complement in-field studies for estimating root respiration.

The average rate of CO2 emission was 964 g CO2/m2/yr, with no significant difference (P<0.05) among cleared and uncleared sites. Microbial respiration and microbial biomass were greater at uncleared compared with those at cleared sites. The Q 10-value of 1.42 (measured for different seasons in a year) for in-field measurements suggested a small response of soil respiration to soil temperature, possibly due to the limited availability of soil moisture and/or organic matter. However, results from the polyhouse experiment suggested greater sensitivity of root respiration to temperature change than for total soil respiration. Since root biomass (herbaceous roots) was greater at the cleared than at uncleared sites, and root respiration increased with an increase in temperature, we speculate that with rising ambient temperature and consequently soil temperature, total soil respiration in cleared pastures will increase at a faster rate than that in uncleared pastures.  相似文献   
54.
Phytoparasitica - Zeugodacus cucurbitae (Coquillett) is an economically significant destructive pest of many vegetable and fruit crops. Peptidase inhibitors are a class of plant proteins that cause...  相似文献   
55.
The effect of different levels of nitrogen N0(0kg/ha), N1(30 kg/ha), N2 (60 kg/ha), and N3 (90 kg/ha) and farmyard manure F0 (0 tonnes/ha), F1 (10 tonnes/ha), and F2 (20 tonnes/ha) on the yield and nutrient composition of spinach and its uptake was investigated on a sandy loam soil. Yield; phosphorus, iron, manganese, zinc, and copper uptakes; and ascorbic acid content increased with the application of both the inorganic nitrogen fertilizer and the farmyard manure, with a maximum at the N3F2 level, i.e. at 90 kg N/ha with 20 tonnes FYM/ha. However, the contents of protein, -carotene, and reducing sugars were maximum at the highest dose of nitrogen without the application of farmyard manure.  相似文献   
56.

Cytoplasmic male sterility (CMS) system has been exploited worldwide in field and vegetable crops. In eggplant, alloplasmic CMS lines were developed through interspecific hybridization between Solanum aethiopicum L.?×?S. melongena L., while the restorer (R) lines were isolated from the reciprocal cross. The knowledge about inheritance of Rf gene is must for its further use in breeding and molecular studies. Therefore, four sets of CMS (D-CMS 291A, D-CMS 99A, D-CMS 5A and D-CMS 72A) and restorer (R 2-1, R 3-4, R 6-2 and R 2596-2) lines were used to develop F1, F2 and backcross progenies, to understand the inheritance mechanism. Phenotyping of all the populations and test of goodness of fit revealed involvement of a single dominant gene (Rf) for fertility restoration. The visual scoring of flowers for male sterility and fertility was further validated with the tests on pollen stainability, germination and index. Among others, media containing 0.5% agar?+?300 ppm calcium nitrate?+?5% sucrose?+?50 mg/l boric acid?+?400 mg/l PEG 4000 furnished the best results for in vitro pollen germination. Differences between and within male sterile and restorer lines were observed for pistil and stamen length and girth, pollen stainability and germination. Stable expression of CGMS and restorer lines in all the generation progenies confirmed their utility in future eggplant breeding programs.

  相似文献   
57.
A wild non-progenitor species from wheat (Triticum aestivum L.) tertiary gene pool, Aegilops peregrina (Hack.) Maire & Weiller accession pau3519 (UUSS), was used for introgression of leaf rust (caused by Puccinia triticina) and stripe rust (caused by Puccinia striiformis f. sp. tritici) resistance in bread wheat. The accession was crossed and backcrossed with hexaploid wheat line Chinese Spring PhI to develop two homozygous BC2F6 wheat-Ae. peregrina introgression lines (ILs), viz., IL pau16058 and IL pau16061, through induced homoeologous recombination. Homozygous lines were screened against six Puccinia triticina and two Puccinia striiformis f. sp. tritici pathotypes at the seedling stage and a mixture of prevalent pathotypes of both species at the adult plant stage. IL pau16061 showed resistance to leaf rust only, whereas IL pau16058 was resistant to both leaf and stripe rust pathotypes throughout plant life. Molecular profiling of these ILs with simple sequence repeat (SSR) markers indicated that alien introgressions were mainly terminal and very few were interstitial. Identification of linked markers with advanced genomic technologies will aid in marker-assisted pyramiding of alien genes in cultivated wheat background.  相似文献   
58.
The present study was undertaken to estimate effect of various genetic and non-genetic factors on persistency of milk production and to identify the most appropriate persistency method that fits best in our environment. In the present study, effects of different non-genetic factors, viz. year, season, days to attain peak yield, and genetic group based on the level of exotic inheritance on persistency of milk yield in crossbred cattle were studied. Data comprised of 686 first lactation daily milk yield records of crossbred cattle that were maintained at GADVASU dairy farm over a period of 25 years from 1991 to 2015 were utilized to calculate persistency coefficients by four methods, viz., Ludwick and Peterson method (P1), Mahadevan method (P2), ratio method (P3), and Prasad et al. method (P4). Overall least squares means for persistency by Ludwick and Peterson method (P1), Mahadevan method (P2), ratio method (P3), and Prasad et al. method (P4) were 0.896?±?0.096, 1.385?±?0.224, 187.207?±?26.398, and 0.621?±?0.098, respectively. Effect of sires was significant (P?<?0.05) on P2 and P4 methods. Effect of genetic group on all four methods was non-significant. Period of calving had significant (P?<?0.01) effect on persistency of milk yield (P2, P3, and P4 methods). Effect of season of calving on persistency of milk yield was found to be significant in all estimates obtained by the four methods. Summer and autumn calvers were most persistent whereas spring and winter calvers were least persistent for (P2, P3, and P4 methods). Persistency of milk yield was significantly (P?<?0.05) affected by days to attain peak yield in P1 and P2 methods. Maximum persistency was obtained in animals attaining peak at 41–57 days of lactation and minimum in <?41 days for Mahadevan method and ratio method. The highest heritability of persistency and minimum value of standard error was estimated as 0.275?±?0.11 for the Mahadevan method followed by the Prasad method (0.197?±?0.10) by half sib correlation method. The maximum coefficient of variation which indicates available variability was estimated as 20.788% for persistency by the Mahadevan method followed by 18.969% for the Prasad method. The highest correlation was also observed between P1 and P3 methods by Spearman’s and Pearson’s correlation for least squares breeding value of the sires. On the basis of heritability, standard error of heritability, and coefficient of variation, it can be concluded that the Mahadevan method followed by the Prasad method suits best to our environment for animals in first lactation as well as they can be utilized for effective selection for higher persistency in crossbred animals of Punjab.  相似文献   
59.
Drought is a severe abiotic stress and the major constraint on wheat (Triticum aestivum L.) productivity world wide. Deciphering the mechanisms of drought tolerance is a challenging task because of the complexity of drought responses, environmental factors and their interactions. The objective of this study was to evaluate the ability of the antioxidative defence system in imparting tolerance against drought‐induced oxidative stress and yield loss in two wheat genotypes, when subjected to long‐term field drought. Drought resulted in an increase in H2O2 accumulation and lipid peroxidation and decrease in ascorbate level in roots and leaves at different plant developmental stages. Drought‐tolerant genotype having higher antioxidative enzymes activities, and ascorbate level was superior to that of sensitive genotype in maintaining lower H2O2 content and lipid peroxidation and higher growth, yield and yield components under water deficit. Various antioxidative enzymes showed positive correlation with ascorbate and negative with H2O2 content. In developing grains, antioxidative defence response was nearly similar among both the genotypes under control condition; however, sensitive genotype failed to modulate the activities of antioxidative enzymes according to the ROS rush under field drought. Poor capacity of the antioxidative defence system in vegetative and reproductive tissues of sensitive genotype seems to be responsible, at least partly, for reduced yield potential under water deficit.  相似文献   
60.
Plant Foods for Human Nutrition - Mahua (Madhuca longifolia) flowers are boon for the local tribes of India and have been successfully utilized traditionally for the value addition, and are very...  相似文献   
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