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991.
Containerized plant production represents an extremely intensive agricultural practice with large amounts of moisture and fertilizer application. Hydro-physical characteristics such as water infiltration, texture and structure, particle size distribution affect the quality of the media used in containerized agricultural systems and the water availability to plants. Water retention characteristics depend on particle size distribution as well as the composition of the media used. Materials with coarser particles allow faster percolation of water and also retain relatively higher amounts moisture per unit weight due to higher porosity, while draining faster due to smaller surface area per unit weight. Faster drainage can result into airflow through coarser materials causing the media to dry. The objectives of this study were to characterize the selected hydro-physical properties of plant growth media that are commonly used by nurseries in South Florida. Characterization of the plant growing media can allow modeling of soil-water interactions and development of best management practices for more efficient use of water and agrochemicals by nurseries. Experimental analyses were performed to characterize the plant growth mixtures in terms of particle size distribution and hydraulic conductivity using three different methods (i.e., constant head permeability, falling head permeability test, and tension infiltrometer test). The saturated hydraulic conductivity of the mixtures measured by constant head method ranged from 0.029 to 0.042 cm/s (104-151 cm/h) and by falling head method ranged from 0.078 to 0.112 cm/s (281-403 cm/h). The saturated hydraulic conductivity of the mixtures measured by tension infiltrometer ranged from 0.02 to 0.34 cm/h. Understanding water retention and permeation characteristics of the plant growing media could assist development of best management practices (BMP) for containerized agricultural systems for efficient management of irrigation water and agrochemical use. 相似文献
992.
In eastern India, cultivation of winter maize is getting popular after rainy season rice and farmers practice irrigation scheduling
of this crop based on critical phenological stages. In this study, crop water stress index of winter maize at different critical
stages wase determined to investigate if phenology-based irrigation scheduling could be optimized further. The components
of the energy budget of the crop stand were computed. The stressed and non-stressed base lines were also developed (between
canopy temperature and vapor pressure deficit) and with the help of base line equation, [(T
c − T
a) = −1.102 VPD − 3.772], crop water stress index (CWSI) was determined from the canopy-air temperature data collected frequently
throughout the growing season. The values of CWSI (varied between 0.42 and 0.67) were noted just before the irrigations were
applied at critical phenological stages. The soil moisture depletion was also measured throughout the crop growing period
and plotted with CWSI at different stages. Study revealed that at one stage (silking), CWSI was much lower (0.42–0.48) than
that of recommended CWSI (0.60) for irrigation scheduling. Therefore, more research is required to further optimize the phenology-based
irrigation scheduling of winter maize in the region. This method is being used now by local producers. The intercepted photosynthetically
active radiation and normalized difference vegetation index over the canopy of the crop were also measured and were found
to correlate better with leaf area index. 相似文献
993.
994.
U. M. Ramesh Ramesh Methre N. V. M. Kumar Ishwarappa S. Katageri S. Anjan Gowda Sateesh Adiger Satish Kumar Yadava Vijay B. R. Lachagari 《Plant Breeding》2019,138(6):880-896
The identification of quantitative trait loci (QTL) across different environments is a prerequisite for marker‐assisted selection (MAS) in crop improvement programmes. CottonSNP63k Illumina infinium array was used for genotyping 178 inter‐specific recombinant inbred lines and the parents, and identified 1,667 homozygous polymorphic markers between the parents. Of these, 1,430 markers were used for the construction of linkage map after removing 237 redundant markers. The genetic map spans a total genetic length of 3,149.8 cM with an average marker interval size of 2.2 cM. The phenotypic data from five environments were analysed separately using inclusive composite interval mapping which identified a total of 56 QTL explaining phenotypic variances (PVE) in the range of 8.18%–28.91%. There were 11 and 24 major QTL found for fibre quality and yield components, respectively. A total of 64 QTL were identified through Multi‐Environment Trials analysis, of which 34 recorded QTL × Environment interactions. 相似文献
995.
Grewal A. S. Singh Avtar Kumar Sanjay Kondal J. K. Kanwar J. R. Kapur J. Sawhney S. M. S. 《Tropical animal health and production》1997,29(4):104S-108S
Tropical Animal Health and Production - Bovine tropical theileriosis is of high incidence in calves below 2 months old in India. TheTheileria cell culture vaccine evolved by the Punjab Agricultural... 相似文献
996.
Kwon Soo-Jeong Roy Swapan Kumar Yu Jang-Hwan Cho Seong-Woo Kim Hag-Hyun Boo Hee-Ock Woo Sun-Hee 《Journal of Crop Science and Biotechnology》2019,22(5):465-474
Journal of Crop Science and Biotechnology - The root of Platycodon grandiflorum is used as traditional oriental medicine in Asian countries since ancient times to treat bronchitis, tonsillitis,... 相似文献
997.
Kwon Soo-Jeong Kim Hye-Rim Roy Swapan Kumar Kim Hyun-Jung Boo Hee-Ock Woo Sun-Hee Kim Hag-Hyun 《Journal of Crop Science and Biotechnology》2019,22(5):481-487
Journal of Crop Science and Biotechnology - Fertilization plays a vital role to enhance productivity in several medicinal plants, including Bellflower. A pot experiment was conducted in 2018 to... 相似文献
998.
温度是影响细菌生长与失活的关键因素,在食品生产中常用来控制致病微生物潜在的风险。但由于不同菌株间个体的差异,细菌在相同温度作用下呈现出不同的失活趋势,这种行为方式称为菌株的失活异质性,容易导致微生物风险控制的不确定性和变异性。比较了19株副溶血性弧菌(16株临床菌株和3株环境菌株)在巴氏消毒温度(65℃)及冷链温度(10℃)作用下的失活情况,并结合Weibull模型,拟合相应的失活参数(t_R值),探究了不同菌株间的失活异质性。在65℃处理条件下,19株副溶血性弧菌的t_R值介于22.62~67.23 s,VPC-1为耐热性最强菌株,而VPC-10为耐热性最弱菌株,热失活参数t_R值最适的概率分布为Normal (44.82, 12.27)。在10℃条件下,t_R值介于113.96~371.38 h,VPC-3为耐冷性最强菌株,VPC-2为耐冷性最弱菌株,冷失活参数t_R值最适的概率分布为Loglogistic (51.45,148.88,4.67)。结果表明,副溶血性弧菌的热失活和冷失活间没有显著的相关性,菌株的失活异质性广泛存在于副溶血性弧菌之中,仅基于单一菌株进行失活模型的拟合,很难描述其整体的失活趋势。同时,初步构建了菌株失活异质性的随机模型,并使用概率分布代替了传统的失活参数。 相似文献
999.
Pinakin Dave Jaydeep Kumar Vikas Kumar Satish Kaur Sawinder Prasad Rasane Sharma Basista Rabina 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(4):576-582
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
1000.
Singh Pushpendra Tripathi Manish Kumar Yasir Mohammad Khare Ruchi Tripathi Manoj Kumar Shrivastava Rahul 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(4):458-466
Plant Foods for Human Nutrition - The severe acute respiratory syndrome is a viral respiratory infection and commonly called as COVID-19, caused by severe acute respiratory syndrome coronavirus-2... 相似文献