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131.
Wheat is one of the most widely cultivated crops and, being the staple diet of more than 40 countries, it plays an imperative role in food security. Wheat has remarkable genetic potential to synchronize its flowering time with favourable environmental conditions. This ability to time its flowering is a key factor for its global adaptability and enables wheat plant to produce satisfactory grain yield under very diverse temperature and soil moisture conditions. Vernalization (Vrn), photoperiod (Ppd) and earliness per se (Eps) are the three genetic systems controlling flowering time in wheat. The objective of this review is to provide comprehensive information on the physiological, molecular and biological aspects of the three genetic constituents of flowering and maturity time in wheat. Reviews written in the past have covered either one of the aspects; and generally focused on one of the three genetic constituents of the flowering time. The current review provides (a) a detailed overview of all three gene systems (vernalization, photoperiod and earliness per se) controlling flowering time, (b) details of the primer sequences, their annealing temperatures and expected amplicon sizes for all known markers of detecting vernalization and photoperiod alleles, and (c) an up to date list of QTLs affecting flowering and/or maturity time in wheat. 相似文献
132.
Estrous expressions in dairy cows have been shortened and weakened. Dairy heifers, on the other hand, may not have had such changes in estrous signs as observed in cows, since they have less stresses than cows. The aim of this study was to describe the duration of estrus in a herd of dairy heifers. A total of 56 Holstein Friesian heifers estrus was synchronized using two different hormonal protocols. They were checked for primary and secondary estrous signs with the help of heat detection devices for 48 h at an interval of 4 h starting at 16.00 hour, one day after PGF2α treatment. Onset and end of standing estrus during 48 h observation period was recorded in 35 of the 44 heifers coming into estrus within 5 days after PGF2α treatment during the observation period. The duration of standing estrus on the average (±SD) was 9.7 ± 5.3 h. Percentage of heifers with standing estrus longer than 12 h was 40%, and 53% showed standing estrus only for 4–8 h. It is indicated that duration of estrus in dairy heifers has been shortened recently. 相似文献
133.
This project was conducted to investigate the comparative efficiency of competitive ELISA (cELISA), standard Agar Gel Immunodiffusion
Test (AGID) and Precipitinogen Inhibition Test (PIT) for the diagnosis of Peste des Petits Ruminants (PPR) in Pakistan. To deal with this, serum samples from 198 sheep and 82 goats were collected from three different government
livestock farms and all the samples were run simultaneously with the three serological tests. The samples found positive for
PPR antibodies through cELISA, AGID and PIT were 96 (34.2%), 60 (21.4%) and 72 (25.7%), respectively. Kappa statistics were
applied to evaluate the concordance between the laboratory-based test (cELISA) and field-based tests (AGID and PIT). Kappa
statistics scores for cELISA versus AGID and PIT were 0.6343 (95% Confidence Interval CI 0.5231–0.7456) and 0.7134 (95% Confidence
Interval CI 0.5987–0.8281), respectively, which indicate a “substantial” agreement between cELISA and AGID and “significant”
agreement between cELISA and PIT. AGID and PIT revealed relative diagnostic sensitivities with cELISA of 59.3% and 69.7% and
relative diagnostic specificities of 98.3% and 97.2%, respectively. The data suggested that for mass screening and control
of PPR, these serological tests proved practical in the absence of cELISA since they have high relative diagnostic specificities
and a satisfactory relative diagnostic sensitivities. 相似文献
134.
Iqra Javid Mahroze Fatima Syed Zakir Hussain Shah Muhammad Afzal 《Aquaculture Nutrition》2021,27(1):217-224
The effect of organic acids (OA) and dicalcium phosphate (Pi) supplementation in the feed of Labeo rohita fingerlings was studied by formulating seven practical diets, designed as D1 with no feed additives {dicalcium phosphorus (Pi) and organic acid (OA) blend} while, D2, D3, D4 and D5 were supplemented with Pi at the graded levels of 5, 10, 15 and 20 g/kg, respectively, whereas D6 and D7 contained blend of OA at 15 and 30 g/kg, respectively. The diet supplemented with OA blend exhibited increase (p < .05) in growth of L. rohita fingerlings compared with the diet supplemented with Pi. The OA supplementation at both levels showed significant improvement in nutrients digestibility and minerals absorption in fingerlings. Moreover, in case of muscle proximate composition, crude fat (CF) and crude protein (CP) were increased (p < .05) with the inclusion of OA blend in the diet while crude ash (CA) was improved by Pi supplementation. Additionally, digestive enzyme activities were not affected (p ? .05) by OA blend supplementation while increased activities were observed in the fingerlings fed with Pi diet. Consequently, supplementation of OA blend in the diet improved the growth performance and nutrient status while Pi enhanced digestive enzyme activities of L. rohita fingerlings. 相似文献
135.
Wira Wisnu Wardani Alimuddin Alimuddin Muhammad Zairin Junior Mia Setiawati Sri Nuryati Muhammad Agus Suprayudi 《Aquaculture Nutrition》2021,27(1):274-286
The experimental diets containing five levels of creatine supplementation, namely control (N = 0 g/kg creatine), B1 (1.00 g/kg glycine), B2 (0.40 g/kg creatine), B3 (0.80 g/kg creatine) and B4 (1.20 g/kg creatine) were tested to red tilapia up to apparent satiation 3 times a day for 56 days. After the feeding trial, fish were stressed by air exposure for challenge test against stress. The results described that creatine supplementation improved final body weight, feed conversion ratio (FCR) and protein retention. Creatine supplementation decreased blood glucose, cholesterol and triglyceride levels (p < .05), indicating more effective usage of non‐protein energy. Furthermore, creatine supplementation also increased plasma insulin levels and upregulated IGF‐1 and GLUT4 gene expressions in the liver significantly; it also improved robustness against stress, which was shown by higher superoxide dismutase, higher postchallenge survival and plasma cortisol, malondialdehyde and lower glucose levels. In conclusion, creatine supplementation at a dose of 0.289–0.389 g/kg diet escalated fish growth and improved robustness against stress via improving the SOD activity in red tilapia. 相似文献
136.
Methyl jasmonate alleviated salinity stress in soybean 总被引:1,自引:0,他引:1
Ji Young Yoon Muhammad Hamayun Su-Kyung Lee In-Jung Lee 《Journal of Crop Science and Biotechnology》2009,12(2):63-68
We studied the role of methyl jasmonate (MeJA) in alleviating NaCl-induced salt stress on soybean growth and development in
hydroponics medium. Soybean seedlings were exposed to 60 mM NaCl stress for 2 weeks, 24 h after the application of 20 and
30 μM MeJA. NaCl stress induced a significant reduction in plant growth, endogenous bioactive gibberellin (GA4), photosynthesis
and transpiration rate, while a marked increase in the endogenous abscisic acid (ABA) and proline contents were recorded.
MeJA application greatly mitigated the adverse effects of NaCl on soybean growth and endogenous hormones. MeJA significantly
increased ABA levels, while the endogenous amount of GA4 was reduced by the application of NaCl. Our study revealed that MeJA
counteracted the negative effects of NaCl stress on plant growth, chlorophyll content, leaf photosynthetic rate, leaf transpiration
rate, and proline content. 相似文献
137.
138.
Ghulam Abbas Tariq Manzoor Khan Jehanzeb Farooq Abid Mahmood Rana Nadeem Abbas Wajad Nazeer Amjad Farooq Zuhair Hasnain Muhammad Naeem Akhtar 《Frontiers of Agriculture in China》2011,5(4):443-449
This research was conducted to explore genetic material that can yield better under salt stress conditions. The experiment
was laid out using 27 upland cotton genotypes in a RCBD 2 factorial arrangement with two replications. Saline water (NaCl
at 20 dS/m) was applied after satisfactory emergence was achieved. The crop was raised to maturity and data relating to yield,
fiber quality and ionic traits were recorded. Analysis of variance showed significant variations in the germplasm. Plant height,
bolls per plant, boll weight, GOT%, staple length, staple strength, K+ and K+/Na+ ratio under salinity stress showed a highly significant correlation with seed-cotton yield. The highest direct effect on
seedcotton yield per plant was exhibited by bolls per plant and boll weight. The results from the correlation and path coefficient
analyses revealed that although the K+/Na+ ratio had a strong positively significant association with seedcotton yield, its direct effect on the seed-cotton yield was
negative and thus selection on the basis of K+/Na+ may not be fruitful. Hence, only indirect selection through bolls per plant and boll weight may be effective in increasing
the seedcotton yield per plant under salinity stress. 相似文献
139.
Shahid Iqbal Awan Muhammad Shahzad Ahmed Jehanzeb Farooq Syed Dilnawaz Ahmad Muhammad Ilyas Asad Hussain Shah Muhammad Fareed Khan Sardar Ali Lutful Hasan 《Frontiers of Agriculture in China》2011,5(4):486-496
An experiment was conducted to access the genetic variability among early vigour and quantitative traits under limited moisture
in F2 generation of a 5 × 5 diallel cross of bread wheat. The results indicated that there was significant genotypic variation
among the genotypes. Additive dominance model revealed full fitness of the data for RL, DSW, FRW, DRW, spike length, and 1000-grain
weight but was partially fit for SL, FSW, R/S, tillers per seedling, plant height, tillers per plant, spikelets per spike,
and grain yield per plant. The partially adequate models for these plant characters might be due to the presence of non-allelic
interaction, linkage, and non-independent distribution of the genes in the parents. Additive genes coupled with moderate to
high narrow sense heritability were involved in the heritage of all the traits, which indicated a higher scope of selection
in early generations. 相似文献
140.
Muhammad Rizwan Shafaqat Ali Muhammad Zia ur Rehman Muhammad Rizwan Javed Arooj Bashir 《Water, air, and soil pollution》2018,229(6):211
Cereal grains such as wheat, rice, and maize are widely consumed as a staple food worldwide. Lead (Pb) is one of the non-essential trace elements and its toxicity in crops especially cereals is a widespread problem. The present review highlighted Pb toxicity in cereal and management strategies to reduce its uptake in plants. Lead toxicity reduced the cereal growth, photosynthesis, nutritional value, yield, and grain quality. The response of cereals to excess varies with plant species, levels of Pb in soil, and growth conditions. Reducing Pb bioavailability in the soil is a viable approach due to its non-degradability either by microbes, chemicals, or other means. Cultivation of low Pb-accumulating cultivars may reduce the risk of Pb toxicity in plants and humans via the food chain. Use of plant growth regulators, microbes, organic, and inorganic amendments might be promising techniques for further decreasing Pb contents in shoot and grains. Soil amendments along with selecting low Pb-accumulating cultivars might be a feasible approach to get cereal grains with low Pb concentrations. Furthermore, most of the studies have been conducted under controlled conditions either in hydroponic or pots and less is known about the effects of Pb management approaches under ambient field conditions. 相似文献