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121.
Mustafa Roma Iqbal Muhammad Javed Hamza Muhammad Rehman Atiq Ur Buzdar Ismail Kamal Hira Mansoor Shahid Amin Imran 《European journal of plant pathology / European Foundation for Plant Pathology》2021,161(4):917-931
European Journal of Plant Pathology - Virus-induced gene silencing (VIGS) is a reverse genetic tool used to identify the function of individual genes by reducing their expression. Here VIGS was... 相似文献
122.
Research progress on the role of melatonin and its receptors in animal reproduction: A comprehensive review
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HS Talpur IB Chandio RD Brohi T Worku Z Rehman D Bhattarai F Ullah L JiaJia L Yang 《Reproduction in domestic animals》2018,53(4):831-849
Melatonin and its receptors play a crucial role in the regulation of the animal reproductive process, primarily in follicular development. However, the role that melatonin performs in regulating hormones related with reproduction remains unclear. Melatonin and its receptors are present both in female and male animals’ organs, such as ovaries, heart, brain and liver. Melatonin regulates ovarian actions and is a key mediator of reproductive actions. Melatonin has numerous effects on animal reproduction, such as protection of gametes and embryos, response to clock genes, immune‐neuroendocrine, reconciliation of seasonal variations in immune function, and silence or blockage of genes. The growth ratio of reproductive illnesses in animals has raised a remarkable concern for the government, animal caretakers and farm managers. In order to resolve this challenging issue, it is very necessary to conduct state‐of‐the‐art research on melatonin and its receptors because melatonin has considerable physiognomies. This review article presents a current contemporary research conducted by numerous researchers from the entire world on the role of melatonin and its receptors in animal reproduction, from the year 1985 to the year 2017. Furthermore, this review shows scientific research challenges related to melatonin receptors and their explanations based on the findings of 172 numerous research articles, and also represents significant proficiencies of melatonin in order to show enthusiastic study direction for animal reproduction researchers. 相似文献
123.
Csaba Tölgyesi Zoltán Bátori Róbert Gallé István Urák Tibor Hartel 《Strength and Conditioning Journal》2018,71(5):571-577
Rangelands with scattered trees are complex and dynamic systems with a long history in Europe. Generally referred to as “wood-pastures,” they are considered to have outstanding conservation value. Thorny shrubs are important for supporting the biodiversity of these wooded rangelands, as well as facilitating the regeneration of trees by acting as nurse species. We assess the direct effects of temporary shrub encroachment under the cover of mature sparse trees on overall plant and habitat diversity. We surveyed the herb layer of the main landscape features of a wood-pasture: open pasture, trees with a grass understory, trees with shrubs, and adjacent forest edges. The herb layer under trees with shrubs resembled that of forest edges more than open pastures and trees with grass. Trees with grass had a higher cover of ruderal species than trees with shrubs, while forest edges and open pastures had a lower cover of them. Forest species were absent from open pastures but were well represented in the other sites. The herb layer of trees with shrubs and forest edges had similar cover values, while trees with grass had a significantly lower cover of herbs than the other types. Trees with shrubs had higher species richness than any of the other three landscape features and had a much higher proportion of diagnostic species. We conclude that the scattered trees and shrubs of the studied silvopastoral system have additive facilitative effects on their understory, probably through modifying the microenvironment and grazing pressure, leading to the formation of temporary diversity hot spots with distinct vegetation. Thus maintaining a moderate level of shrub-encroachment under sparse trees is recommended for not only creating safe havens for tree recruitment but also increasing the overall species and habitat diversity of wood-pastures. 相似文献
124.
Rizwan Muhammad Noureen Shamaila Ali Shafaqat Anwar Sarwat Rehman Muhammad Zia ur Qayyum Muhammad Farooq Hussain Azhar 《Journal of Soils and Sediments》2019,19(11):3749-3759
Journal of Soils and Sediments - The majority studies used the biochar or nanoparticles alone in metal-contaminated soils while less is known about the combined use of these amendments in... 相似文献
125.
为了克服确定作物需水量所遇到的困难,该文介绍一种简单、可靠、易掌握、实用的生物气候测定方法.该方法根据被测地的土壤、气候和作物参数,得到玉米在生长季节的光水热系数平均值为0.15mm/℃.该方法应用于南斯拉夫伏霍基拉省取得成功.由于光水热系数是由各地的特殊条件确定的,只要确定了该系数,该方法可在任何地方应用.灌溉时间和灌溉强度以及干旱的发生都可由该方法确定.玉米生长期的需水量为467mm. 相似文献
126.
Aman Ullah Muhammad Farooq Asif Nadeem Abdul Rehman Saeed A. Asad Ahmad Nawaz 《Paddy and Water Environment》2017,15(3):563-572
Manganese (Mn) deficiency is prevalent in rice-growing regions resulting in poor paddy yield and human health. In this study, role of Mn, applied through various methods, in improving the productivity and grain biofortification of fine grain aromatic rice was evaluated. Manganese was delivered as soil application (SA) (0.5 kg ha?1), foliar spray (FA) (0.02 M Mn), seed priming (SP) (0.1 M Mn) and seed coating (SC) (2 g Mn kg?1 seed) in conventional (puddled transplanted flooded rice) and conservation (direct seeded aerobic rice) production systems at two different sites (Faisalabad, Sheikhupura) in Punjab, Pakistan. Manganese application, through either method, improved the grain yield and grain Mn contents of fine grain aromatic rice grown in both production systems at both sites. However, Mn application as SC and FA was the most beneficial and cost effective in improving the productivity and grain biofortification in this regard. Overall, order of improvement in grain yield was SC (3.85 t ha?1) > FA (3.72 t ha?1) > SP (3.61 t ha?1) > SA (3.36 t ha?1). Maximum net benefits and benefit–cost ratio were obtained through Mn SC in flooded field at Faisalabad, which was followed by Mn SP in direct seeded aerobic rice at the same site. However, maximum marginal rate of return was noted with Mn SC in direct seeded aerobic rice at both sites. In crux, Mn nutrition improved the productivity and grain biofortification of fine grain aromatic rice grown in both conventional and conservation production systems. However, Mn application as seed treatment (SC or SP) was the most cost effective and economical. 相似文献
127.
Seed Priming Influence on Early Crop Growth,Phenological Development and Yield Performance of Linola (Linum usitatissimum L.)
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Hafeez ur Rehman Muhammad Qaiser Nawaz Shahzad Maqsood Ahmed Basra Irfan Afzal Azra Yasmeen Fayyaz ul-Hassan 《农业科学学报》2014,13(5):990-996
Reduced early crop growth and limited branching are amongst yield limiting factors of linola. Field response of seed priming treatments viz. 50 mmol L−1 salicylic acid (SA), 2.2% CaCl2 and 3.3% moringa leaf extract (MLE) including untreated dry and hydropriming controls was evaluated on early crop growth and yield performance of linola. Osmopriming with CaCl2 reduced emergence time and produced the highest seedling fresh and dry weights including Chl. a contents. Osmopriming with CaCl2 reduced crop branching and flowering and maturity times and had the maximum plant height, number of branches, tillers, pods and seeds per pod followed by MLE. Increase in seed weight, biological and seed yields was 9.30, 34.16 and 39.49%, harvest index (4.12%) and oil contents (13.39%) for CaCl2 osmopriming. Positive relationship between emergence and seedling vigor traits, 100-seed weight, seed yield with maturity time, 100-seed weight and seed yield were found. The study concludes that seed osmopriming with CaCl2 or MLE can play significant role to improve early crop growth and seed yields of linola. 相似文献
128.
Ullah Najeeb Daniel K. Y. Tan Michael P. Bange 《Archives of Agronomy and Soil Science》2016,62(8):1136-1146
Increased ethylene biosynthesis in cotton tissues have been associated with accelerated fruit abscission and yield losses in waterlogged cotton. In a series of glasshouse and field experiments, we investigated the effect of various application rates (0, 50, 100 and 150 [active ingredient, ai] ha?1) and time (pre- and post-waterlogging) of an anti-ethylene agent, aminoethoxyvinylglycine (AVG) on the growth and yield of cotton. The glasshouse study suggested that AVG (100–150 g [ai] ha?1) applied 24 h prior to waterlogging can increase growth and fruit retention (FR) of waterlogged (WL) and non-waterlogged (NWL) cotton. The positive effects of AVG were further validated in two years of field studies, suggesting that AVG (125 g [ai] ha?1) applied at an early reproductive phase of cotton can significantly increase cotton yield under WL (13%, averaged over two years) and NWL (9%, averaged over two years) environments. Yield increase in AVG-treated cotton was associated with increased number of bolls, boll weight and FR. On the other hand, no further improvement in cotton yield under higher AVG concentration (150 g [ai] ha?1) indicated the saturation of AVG on ethylene inhibition. Thus, appropriate AVG concentration and application timing may help overcome waterlogging-induced yield losses in cotton production systems. 相似文献
129.
Fifty-five mungbean lines were evaluated for days to maturity and grain yield per plant. This material showed considerable
range of variability for the target traits. Eight genetically diverse parents were selected and used for a full diallel set
of crosses to study the mode of inheritance for earliness related parameters (days to flowering, days to maturity and length
of reproductive phase) during summer 2005. The F1 generation of these crosses was sown during the spring of 2006 and the selfed seeds were used to raise the F2 generation during kharif season. The data recorded from two generations were subjected to genetic analysis. The formal ANOVA
showed the significance of both additive and dominance effects for all the traits in both generations. Significance of D,
H1 and H2 components also confirmed the contribution of both additive and dominance effects in controlling the inheritance of these
traits. The estimates of narrow sense heritability were low to moderate except higher estimates for days to maturity in F2 generation, while the broad sense heritability estimates were relatively higher. Seasonal and environmental effects were
also found to be significant. In view of the complex nature of gene action for earliness, it is suggested that breeders should
look for transgressive recombinants of earliness and other desirable attributes in later segregating generations to gain higher
genetic advance. The variety NM92 was found to be the best source of earliness in mungbean breeding. 相似文献
130.
Rising temperatures are a major threat to global wheat production, particularly when accompanied by other abiotic stressors such as mineral nutrient deficiencies. This study aimed to quantify the effects of supra‐optimal temperature on growth, photosynthetic performance, and antioxidative responses in bread wheat cultivars grown under varied zinc (Zn) supply. Two bread wheat cultivars (Triticum aestivum L., cvs. Lasani‐2008 and Faisalabad‐2008) with varied responsiveness to Zn supply and drought tolerance were cultured in nutrient solution with low (0.1 µM) or adequate (1.0 µM) Zn under optimal (25/20°C day/night) or supra‐optimal (36/28°C day/night) temperature regimes. Supra‐optimal temperature severely reduced root but not shoot biomass, whereas low Zn reduced shoot as well as root biomass. Shoot‐to‐root biomass ratio was reduced under low Zn but increased under supra‐optimal temperature. Supra‐optimal temperature inhibited root elongation and volume particularly in plants supplied with low Zn. In both cultivars, Zn efficiency index was reduced by supra‐optimal temperature, whereas heat tolerance index was reduced by low Zn supply. Supra‐optimal temperature decreased photosynthesis, quantum yield, and chlorophyll density in low‐Zn but not in adequate‐Zn plants. In comparison, low Zn decreased specific activities of superoxide dismutase (SOD) and ascorbate peroxidase (APX) and increased glutathione reductase (GR), where supra‐optimal temperature increased SOD, decreased GR and did not change APX activity in leaves and roots. Moreover, supra‐optimal temperature severely reduced shoot Zn concentration and Zn uptake per plant specifically under adequate Zn supply. Overall, supra‐optimal temperature exacerbated adverse effects of low Zn supply, resulting in severe reductions in growth traits viz. shoot and root biomass, root length and volume, and consequently impeded Zn uptake, enhanced oxidative stress and impaired photosynthetic performance. Adequate Zn nutrition is crucial to prevent yield loss in wheat cultivated under supra‐optimal temperatures. 相似文献