Compatibility of root growth and tuber production of potato cultivars with dynamic and static water‐saving irrigation managements          下载免费PDF全文

S. H. Ahmadi  M. Agharezaee  A. A. Kamgar‐Haghighi  A. R. Sepaskhah 《Soil Use and Management》2017,33(1):106-119

The important root characteristics of root length density (RLD) and root mass density (RMD) generally differ among irrigation managements and potato cultivars. The objective of this study was to investigate the RLD and RMD variations and their functional relationships with gross potato tuber yield for two commercial potato cultivars, Agria and Sante, under different irrigation strategies. Full irrigation and water‐saving irrigation strategies, deficit and partial root drying irrigations, were applied statically (S) and dynamically (D) based on daily crop evapotranspiration. Results showed that SPRD had significantly greater RLD (3.64 cm/cm³) and RMD (132.7 μg/cm³) than other irrigation treatments. Between the potato cultivars, Agria had significantly larger values of RLD (3.50 cm/cm³) and RMD (138.7 μg/cm³) than Sante. The functional relationship between the root growth characteristics and tuber yield showed that under water‐saving irrigations, Agria increased root mass at the expense of gross tuber yield but Sante increased root mass to maintain larger gross tuber yields. However, Agria produced more roots and gross tuber yield than Sante, and it is concluded that Agria is a more drought‐tolerant potato cultivar, which is recommended for tuber production in regions where water might be scarce. It was shown that larger root production in potatoes was associated with improved tolerance to water stress.  相似文献   

MENSURATION OF THE NORMAL PITUITARY GLAND FROM MAGNETIC RESONANCE IMAGES IN 96 DOGS     

Hege  Kippenes  DVM  Patrick R.  Gavin  DVM  PhD  Susan L.  Kraft  DVM  PhD  Ronald D.  Sande  DVM  MS  PhD  Russell L.  Tucker  DVM 《Veterinary radiology & ultrasound》2001,42(2):130-133

The pituitary gland was measured from transverse magnetic resonance T1-weighted images after Gadolinium administration in 96 dogs weighing from 13 to 45 kg. The measurements were done by hand with calipers. The mean (+/- standard deviation) pituitary gland height was 5.1 mm (+/-0.9 mm). The mean width was 6.4 mm (+/- 1.1 mm). The correlation coefficient between pituitary and brain measurements, between pituitary measurement and body weight, and brain measurements and body weight was 0.0 to 0.3. A hyperintense region was present on T1-weighted images in the center of the pituitary gland in 64% of the dogs. At necropsy the pituitary glands were grossly and histologically normal. No pituitary gland measurements were performed at necropsy.  相似文献   

Mid-storage and pre-sowing seed treatments for lettuce and carrot     

Dolly Pan  R.N. Basu 《Scientia Horticulturae》1985,25(1):11-19

Mid-storage hydration-dehydration treatments with medium-vigour lettuce seed very effectively reduced physiological deterioration in storage and ultimately showed better field emergence and final yield. Soaking-drying treatment of high-vigour lettuce seed was not effective. Pre-sowing treatment of medium-vigour lettuce seed, though less effective than mid-storage treatment, gave better field performance, but high-vigour seed did not benefit from the treatment. For carrot, both mid-storage and pre-sowing seed treatments proved beneficial, with the former showing better performance than the latter. Unlike lettuce, well-preserved carrot seed responded positively to the pre-sowing treatment.  相似文献   

猪场废水的生物处理技术及其效果   总被引：13，自引：0，他引：13  

彭里  王定勇 《家畜生态》2003,24(2):67-69,72

规模化养猪场所产生的废水污染，已成我国农村面临污染的重要来源。针对这种污染，近年来出现了多种养猪场废水处理法，其中研究和应用最广的是生物处理法。本文通过对目前国内猪场废水生物处理法的现状分析后认为：用生物处理法处理猪场废水是今后猪场废水处理的发展方向；而生物处理法自身的发展方向是混合处理法；计算机和生物工程技术将进一步与生物处理法相结合运用于猪场废水处理。  相似文献   

桑苗圃和桑园的化学除草     

黄健明  仇广泰  薛彦明 《蚕桑通报》2001,32(1):27-28

用氟乐灵和精稳杀得或高效盖草能进行桑苗圃除草，用草甘磷和乙草胺混合进行桑园除草，可有效地防除杂草。  相似文献   

Study on Site-specific Nutrient Management in Cotton Field     

YANG Li-ping  Jiang Cheng  JIN Ji-yun  ZHANG Feng-ming 《中国农业科学(英文版)》2001,(1):102-106

The study on the characteristics of spatial variability of soil nutrients and fertilizer recommendations in cotton field under certain conditions of agricultural management was conducted with GIS and systematic approach for soil nutrient constrains. The results showed that of the spatial variability of soil nutrient was greatly related to the management condition of previous crops. Grid sampling and variable rate application technology (VRAT) were the tools that would hopefully increase fertilizer efficiency. The fertilizers were applied where they were needed and at proper rate. Balance fertilization demonstration showed that fertilizer recommendations according to the available nutrient level in soil could decrease fertilizer cost with 657.4 yuan / ha and increase seed cotton yield by 19.8%. A net profit of the balanced fertilization was 5314.9 yuan / ha higher than that of local fertilization practice.  相似文献   

The Effect of Detopping the Field Bean Plants (Vicia faba L. minor) and Lack of the Pod Setting on the Symbiosis with Root Nodule Bacteria     

W. Filek    F. Dubert  M. Kaminski 《Journal of Agronomy and Crop Science》1996,176(1):39-45

The plants of field bean var. Nadwiślaνski were detopped after about 1 month since the beginning of flowering and after that all flower buds were removed from some plants. The effect of a change in the trophic balance on the setting and subsequent growth of root nodules was studied.
The removal of pods had the greater effect on the increase in the weight of the remaining organs than the detopping of plants. Detopping retarded the ageing of the plants and delayed the phase of the greatest reduction of the number of pods. The detopping of plants revealed their considerable compensative possibilities in terms of production of the pod weight and the potential of leaves for biomass production. The data obtained indicate that plant detopping may disturb the root–bacteria exchange of signals, necessary to initiate the nodule development, while the further growth of nodules depends, above all, on the amount of available photosynthates.
A very high correlation between the dry weight of the whole plant to the dry weight of leaves ratio and the weight of nodules was observed. It proves the importance of the trophic balance of the plant for the root nodule weight production.  相似文献   

乙草胺防除辣椒田杂草的药效试验   总被引：1，自引：0，他引：1  

李茹  赵桂东  周玉梅 《安徽农业科学》2001,29(5):628-628

50 %乙草胺EC 12 0 0、15 0 0ml/hm2 在辣椒苗移栽前 1d对土壤用药 ,对辣椒安全 ,除草效果在 75 .0 %～ 82 .6 %之间 ;乙草胺对禾本科杂草的防效好于阔叶草  相似文献   

河北坝上农田垄向对土壤风蚀的影响   总被引：3，自引：0，他引：3  

荣姣凤  高焕文  王晓燕 《中国农业大学学报》2004,9(3):13-15

在河北省坝上选择试验区 ,利用移动式风洞研究了农田起垄方向对土壤风蚀的影响。结果表明 ,农田起垄方向对土壤风蚀具有影响作用 :垄向与风向成 0°时风蚀量最大 ,90°时风蚀量最小 ;在 15m·s-1风速和 3cm表土含水率为 4 5 %的条件下 ,垄向与风向成 0°时的风蚀量为 90°时的 4 8倍。为减轻土壤风蚀危害 ,在河北坝上地区农田起垄的方向宜采用与自然风向NW (西北风向 ,315°)成 90°,即东北方向 4 5°。  相似文献   

MAGNETIC RESONANCE IMAGING FEATURES OF EQUINE NIGROPALLIDAL ENCEPHALOMALACIA     

Sean G.  Sanders  DVM  Russell L.  Tucker  DVM  Rodney S.  Bagley  DVM  Patrick R.  Gavin  DVM  PhD 《Veterinary radiology & ultrasound》2001,42(4):291-296

Magnetic resonance imaging (MR) was used to make a diagnosis of equine nigropallidal encephalomalacia in a horse. Equine nigropallidal encephalomalacia is a neurodegenerative disease that has many characteristics with Parkinson-like diseases in humans. Historically, horses were euthanized based on clinical signs and exposure to the toxic weed, yellow star thistle (Centaurea solstitialis). Previously, the disease has only been confirmed on necropsy. MR imaging can provide accurate and sensitive visualization of typical lesions seen in the brain of horses affected with equine nigropallidal encephalomalacia. Lesions were seen on T1-weighted, T2-weighted and proton density images. There was no contrast enhancement following Gd-DTPA administration. Lesions seen on MR were confirmed at necropsy. Using MR to confirm a diagnosis of equine nigropallidal encephalomalacia will prevent unnecessary suffering of horses and expense to owners that would otherwise incur, while further diagnostics are performed.  相似文献