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941.
Nasreen Naz Ikramullah Khan Bakhtiar Gul Gohar Ayub Farooq Jan Nawaz Jang Muhammad Shuaib 《农业工程》2019,39(1):30-35
A field trail was carried out at the University of Agriculture Peshawar during spring, 2013 in order to evaluate the effect of different levels of phosphorus fertilizer and various planting times on the growth and development of tomato. The main objective of the research work was to investigate the best sowing time for tomato in combination with suitable dose of P fertilizer in order to get maximum yield of tomato in the climatic conditions of Peshawar. RCB Design with split plot arrangements was used in the trail. The main factor (phosphorous levels of 0, 90, 110, 130) was allotted to main plots while sowing dates in sub plots. A total twelve treatment were replicated thrice. Maximum days to flowering (39.583?days) and fruiting (46.167?days) obtained in the late sowing. Minimum days to flowering (39), minimum days to fruiting (38.778?days) were taken by the early sowing. Maximum number of branches (27.778), maximum fruit length (6.0222), maximum fruit with (6.1667), maximum fruit yield (24.653?tons?ha?1) was produced when the plot fertilize with 130?kg?P?ha?1. Maximum number of fruit?plant?1 (29.778) were produced with application of 130?kg?P?ha?1, minimum number of fruits (23.667?cm), fruit width (3.778?cm), fruit length (4.3667?cm), plant height (56.300?cm) were obtained from the controlled treatment. Among the various treatment studied in experiment, it is concluded that early planting of the tomato in the summer season i.e. in the start of March and the use of higher dose of P (130?kg?P?ha?1) is very beneficial for the excellent growth, development and yield of tomato crop. 相似文献
942.
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944.
The 1H nuclear magnetic resonance (1H-nmr) spectra of aqueous solutions of butyryl-CoA (Bu-CoA), indoleacetyl-CoA (IA-CoA), and phenylacetyl-CoA (PA-CoA) were examined at various concentrations and temperatures and compared to spectra of acetyl-CoA (Ac-CoA) and benzoyl-CoA (Bz-CoA) in order to determine to what extent, if any, each acyl-CoA compound exists in an intramolecular folded conformation. It was found previously that Ac-CoA exists predominantly in an extended conformation, whereas Bz-CoA is folded (Mieyal et al., J. Biol. Chem.249, 2633 (1974)). The present study showed: (a_ the solution behavior of Bu-CoA was essentially indistinguishable from that of Ac-CoA; thus both of these aliphatic CoA esters probably exist as extended molecules; (b) IA-CoA does form an intramolecular adenyl-indolyl complex, but the folded/unfolded ratio is only about one-half of that for Bz-CoA at physiological temperature; (c) PA-CoA apparently exists predominantly as an unfolded molecule. The diminished tendency of PA-CoA and IA-CoA to fold is probably related to the rotational mobility about the bond adjoining the respective arylmethylene group to the carbonyl moiety of the thioester link. Concentration-independent effects of the phenyl and indolyl ring currents on the 1H-nmr signals of particular pantotheinyl methylene groups in PA-CoA and IA-CoA, respectively, are consistent with this conclusion. The outstanding conformational difference between the closely related Bz-CoA (folded) and PA-CoA (unfolded) molecules may provide insight regarding the nature of the binding sites for these molecules on the specific N-acyltransferase enzymes for which they are the best substrates (Webster et al., J. Biol. Chem.251, 3352 (1976)). 相似文献
945.
Mahmoud F. Seleiman Muhammad Talha Aslam Bushra Ahmed Alhammad Muhammad Umair Hassan Rizwan Maqbool Muhammad Umer Chattha Imran Khan Harun Ireri Gitari Omer S. Uslu Rana Roy Martin Leonardo Battaglia 《Phyton》2022,91(4):667-694
Salinity stress is a major threat to global food production and its intensity is continuously increasing because of
anthropogenic activities. Wheat is a staple food and a source of carbohydrates and calories for the majority of
people across the globe. However, wheat productivity is adversely affected by salt stress, which is associated with
a reduction in germination, growth, altered reproductive behavior and enzymatic activity, disrupted photosynthesis, hormonal imbalance, oxidative stress, and yield reductions. Thus, a better understanding of wheat (plant)
behavior to salinity stress has essential implications to devise counter and alleviation measures to cope with salt
stress. Different approaches including the selection of suitable cultivars, conventional breeding, and molecular
techniques can be used for facing salt stress tolerance. However, these techniques are tedious, costly, and
labor-intensive. Management practices are still helpful to improve the wheat performance under salinity stress.
Use of arbuscular mycorrhizal fungi, plant growth-promoting rhizobacteria, and exogenous application of phytohormones, seed priming, and nutrient management are important tools to improve wheat performance under
salinity stress. In this paper, we discussed the effect of salinity stress on the wheat crop, possible mechanisms to
deal with salinity stress, and management options to improve wheat performance under salinity conditions. 相似文献
946.
Iqra Ishaaq Muhammad Umer Farooq Syeda Anjum Tahira Rizwana Maqbool Celaleddin Barutçular Muhammad Yasir Saira Bano Zaid Ulhassan Ghassan Zahid Muhammad Ahsan Asghar Sajad Hussain Kocsy Gabor Ulkar Ibrahimova Jianqing Zhu Anshu Rastogi 《Phyton》2022,91(12):2733-2758
Drought is the major detrimental environmental factor for wheat (Triticum aestivum L.) production. The exploration of genetic patterns underlying drought tolerance is of great significance. Here we report the gene actions controlling the phenological traits using the line × tester model studying 27 crosses and 12 parents under normal irrigation and drought conditions. The results interpreted via multiple analysis (mean performance, correlations, principal component, genetic analysis, heterotic and heterobeltiotic potential) disclosed highly significant differences among germplasm. The phenological waxiness traits (glume, boom, and sheath) were strongly interlinked. Flag leaf area exhibits a positive association with peduncle and spike length under drought. The growing degree days (heat-units) greatly influence spikelets and grains per spike, however, the grain yield/plant was significantly reduced (17.44 g to 13.25 g) under drought. The principal components based on eigenvalue indicated significant PCs (first-seven) accounted for 79.9% and 73.9% of total variability under normal irrigation and drought, respectively. The investigated yield traits showed complex genetic behaviour. The genetic advance confronted a moderate to high heritability for spikelets/spike and grain yield/plant. The traits conditioned by dominant genetic effects in normal irrigation were inversely controlled by additive genetic effects under drought and vice versa. The magnitude of dominance effects for phenological and yield traits, i.e., leaf twist, auricle hairiness, grain yield/plant, spikelets, and grains/spike suggests that selection by the pedigree method is appropriate for improving these traits under normal irrigation conditions and could serve as an indirect selection index for improving yield-oriented traits in wheat populations for drought tolerance. However, the phenotypic selection could be more than effective for traits conditioned by additive genetic effects under drought. We suggest five significant cross combinations based on heterotic and heterobeltiotic potential of wheat genotypes for improved yield and enhanced biological production of wheat in advanced generations under drought. 相似文献
947.
Zhang Xiaoyun Tahir Muhammad Mobeen Li Shaohuan Tang Ting Mao Jiangping Li Ke Shao Yun Yang Weiwei Niu Jianxin Zhang Dong 《Plant Cell, Tissue and Organ Culture》2022,148(1):23-34
Plant Cell, Tissue and Organ Culture (PCTOC) - Lateral roots (LRs) are critical for plant stress tolerance and productivity. Understanding how hormones and genes interact in a fluctuating... 相似文献
948.
Farouq A. A. Ismail H. Y. Rabah A. B. Muhammad A. B. Ibrahim U. B. Fardami A. Y. 《Plant and Soil》2022,477(1-2):759-777
Plant and Soil - To understand the influence of cowpea on its rhizosphere physicochemical and biological conditions. Pristine soil samples were contaminated with Bonny-Light crude oil and viable... 相似文献
949.
The decomposition of soil organic carbon (SOC) plays a critical role in regulating atmospheric CO2 concentrations and climate dynamics. However, the mechanisms and factors controlling SOC decomposition are still not
fully understood. Here, we conducted a 60 days incubation experiment to test the effects of physical disturbance
and nitrogen (N) addition on SOC decomposition. N addition increased the concentration of NO3- by 51% in the
soil, but had little effect on the concentration of NH4+. N addition inhibited SOC decomposition, but such an
effect differed between disturbed and undisturbed soils. In disturbed and undisturbed soils, application of N
decreased SOC decomposition by 37% and 15%, respectively. One possible explanation is that extra N input suppressed microbial N mining and/or increased the stability of soil organic matter by promoting the formation of
soil aggregates and incorporating part of the inorganic N into organic matter, and consequently decreased microbial mineralization of soil organic matter. Physical disturbance intensified the inhibition of N on SOC decomposition, likely because physical disturbance allowed the added N to be better exposed to soil microbes and
consequently increased the availability of added N. We conclude that physical disturbance and N play important
roles in modulating the stability of SOC. 相似文献
950.
Hua-Feng Wang Xiaoting Xu Xia-Lan Cheng Yunpeng Liu Ao Luo Tong Lyu Wen-Long Wang Mir Muhammad Nizamani Zhiheng Wang 《Journal of Plant Ecology》2022,15(6):1142
Understanding large-scale patterns of biodiversity and their drivers remains central in ecology. Many hypotheses
have been proposed, including hydrothermal dynamic hypothesis, tropical niche conservatism hypothesis, Janzen’s
hypothesis and a combination model containing energy, water, seasonality and habitat heterogeneity. Yet, their
relative contributions to groups with different lifeforms and range sizes remain controversial, which have limited
our ability to understand the general mechanisms underlying species richness patterns. Here we evaluated how
lifeforms and species range sizes influenced the relative contributions of these three hypotheses to species richness
patterns of a tropical family Moraceae. The distribution data of Moraceae species at a spatial resolution of 50km
×50 km and their lifeforms (i.e. shrubs, small trees and large trees) were compiled. The species richness patterns
were estimated for the entire family, different life forms and species with different range sizes separately. The effects
of environmental variables on species richness were analyzed, and relative contributions of different hypotheses
were evaluated across life forms and species range size groups. The species richness patterns were consistent across
different species groups and the species richness was the highest in Sichuan, Guangzhou and Hainan provinces,
making these provinces the hotspots of this family. Climate seasonality is the primary factor in determining richness
variation of Moraceae. The best combination model gave the largest explanatory power for Moraceae species
richness across each group of range size and life forms followed by the hydrothermal dynamic hypothesis, Janzen’s
hypothesis and tropical niche conservatism hypothesis. All these models has a large shared effects but a low
independent effect (< 5%), except rare species. These findings suggest unique patterns and mechanisms underlying
rare species richness and provide a theoretical basis for protection of the Moraceae species in China. 相似文献