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1.
2.
Potato water use and yield under furrow irrigation 总被引:3,自引:0,他引:3
Field experiments were conducted to study the effects of plant-furrow treatments and levels of irrigation on potato (Solanum tuberosum L.) water use, yield, and water-use efficiency. The experiments were carried out under deficit irrigation conditions in a sandy loam soil of eastern India in the winter seasons of 1991/92, 1992/93, and 1993/94. Two plant-furrow treatments and two levels of irrigation were considered. The two plant-furrow treatments were F1 - furrows with single row of planting in each ridge with 45 cm distance between adjacent ridges, and F2 - furrows with double rows of planting spaced 30 cm apart in each ridge with 60 cm distance between adjacent ridges. The two levels of irrigation (LOI) were I1 - 0.9 IW/CPE and I2 - 1.2 IW/CPE, where IW is irrigation water of 5 cm and CPE is cumulative pan evaporation. Treatment F2 produced highest tuber yield in all years with average value of 10,610 kg ha -1 and 12,780 kg ha -1 at LOI of I1 and I2, respectively. On average, six irrigations with a total of 25 cm, and seven irrigations with a total of 30 cm were required for both treatments F1 and F2 at LOI of I1 and I2, respectively. Treatment F2 resulted in a significantly higher number of branches and tubers per plant, foliage coverage and water-use efficiency for both irrigation levels than treatment F1. Average daily crop evapotranspiration was found to range from 1.1 to 3.4 mm and from 1.2 to 3.9 mm for treatment F1 and from 1.1 to 3.6 mm and from 1.2 to 4.0 mm for treatment F2 at LOI of I1 and I2, respectively. 相似文献
3.
R. Ramesh Kumar L. Prasanna Anjaneya ReddyJ. Vinay Kumar K. KomaraiahS. Purnanand K.P. Sastry 《Industrial Crops and Products》2012,35(1):199-202
Ashwagandha (Withania somnifera) is an important medicinal plant and its dried roots are used in traditional systems of medicine. The market price of roots is determined by physical (textural) quality. Brittle roots with high starch and low fiber are considered to be superior because of ease in grinding. Genetic diversity studies based on root textural parameters have not been done so far. So the present study was designed to assess genetic diversity for morphometric traits and root textural quality parameters among two morphologically distinct groups: Poshita and Nagore. The PCA separated the morphometric and root texture variables distinctly into two different principal components: PC-1 and PC-2 respectively, indicating that both are negatively associated. All the morphotypes in Poshita group showed high positive loadings in PC-1 indicating that component genotypes are high root yielding. Nagore morphotypes were low yielding but the root texture was good. Clustering of morphotypes grouped Poshita and Nagore separately with high inter-cluster distances indicating that both groups are highly divergent from each other, suggesting that there is sufficient scope for varietal improvement through hybridization. 相似文献
4.
Soudamini Panda M. Sharmila K. Ramanand D. Panda N. Sethunathan 《Pest management science》1988,23(3):199-207
The persistence of carbofuran (2, 3-dihydro-2, 2-dimethylbenzofuran-7-yl methylcarbamate) and the β- and γ-isomers of HCH (hexachlorocyclohexane) applied to surface (oxidised) and sub-surface (reduced) layers of a flooded soil was studied using radiolabelled insecticides. In one experiment, these compounds were placed in the surface (2–5 mm) and sub-surface (10–15 cm) layers of 10-day flooded soil columns. HCH isomers were unstable under flooded soil conditions irrespective of their placement, but disappeared slightly faster when applied to the sub-surface layer, possibly due to the more reduced conditions prevailing. In contrast, sub-surface-applied carbofuran was more stable than surface-applied carbofuran. The decreased stability of surface-applied carbofuran may be due to a relatively higher pH in the surface layer and in the flood water which was in immediate contact with the surface layer. In another experiment, surface and sub-surface soil samples were collected from a rice field which had been flooded for 30 days. These soils were then again flooded under laboratory conditions prior to addition of carbofuran and β-HCH. Upon submergence, both surface and sub-surface soil samples attained almost equally reduced conditions. In flooded surface soil samples, more rapid degradation not only of carbofuran but also of β-HCH occurred, compared with similarly incubated sub-surface soil samples. 相似文献
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研究表明,雏鸡出壳后立即进食会更健康,且在其一生中会有一个良好的开端。在近三十年中,选择育种已经显著地提高了肉用仔鸡的生产性能。现代肉鸡不但拥有较快的生长速度, 相似文献
7.
The reported study aimed at developing an integrated management strategy for irrigation water and fertilizers in case of wheat crop in a sub-tropical sub-humid region. Field experiments were conducted on wheat crop (cultivar Sonalika) during the years 2002–2003, 2003–2004 and 2004–2005. Each experiment included four fertilizer treatments and three irrigation treatments during the wheat growth period. During the experiment, the irrigation treatments considered were I1 = 10% maximum allowable depletion (MAD) of available soil water (ASW); I2 = 40% MAD of ASW; I3 = 60% MAD of ASW. The fertilizer treatments considered in the experiments were F1 = control treatment with N:P2O5:K2O as 0:0:0 kg ha−1, F2 = fertilizer application of N:P2O5:K2O as 80:40:40 kg ha−1; F3 = fertilizer application of N:P2O5:K2O as 120:60:60 kg ha−1 and F4 = fertilizer application of N:P2O5:K2O as 160:80:80 kg ha−1. In this study CERES-wheat crop growth model of the DSSAT v4.0 was used to simulate the growth, development and yield of wheat crop using soil, daily weather and management inputs, to aid farmers and decision makers in developing strategies for effective management of inputs. The results of the investigation revealed that magnitudes of grain yield, straw yield and maximum LAI of wheat crop were higher in low volume high frequency irrigation (I1) than the high volume low frequency irrigation (I3). The grain yield, straw yield and maximum LAI increased with increase in fertilization rate for the wheat crop. The results also revealed that increase in level of fertilization increased water use efficiency (WUE) considerably. However, WUE of the I2 irrigation schedule was comparatively higher than the I1 and I3 irrigation schedules due to higher grain yield per unit use of water. Therefore, irrigation schedule with 40% maximum allowable depletion of available soil water (I2) could safely be maintained during the non-critical stages to save water without sacrificing the crop yield. Increase in level of fertilization increases the WUE but it will cause environmental problem beyond certain limit. The calibrated CERES-wheat model could predict the grain yield, straw yield and maximum LAI of wheat crop with considerable accuracy and therefore can be recommended for decision-making in similar regions. 相似文献
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9.
Downy mildews cause considerable damage to maize (Zea mays L.) worldwide, particularly in the tropical Asia. We have evaluated a set of 42 tropical/sub-tropical maize inbred lines
developed in different countries in Asia (India, Thailand and Philippines), and Mexico, for analysing the genetic variability
for resistance to sorghum downy mildew [Peronosclerospora sorghi; SDM] and Rajasthan downy mildew [P. heteropogoni; RDM]. Experiments were carried out in replicated trials under artificial infection in field conditions against SDM and RDM
at Mandya in Karnataka, India, and Udaipur in Rajasthan, India, respectively, during 1999 and 2000. The study resulted in
identification of five inbred lines offering consistent and strong resistance to both SDM and RDM, while several inbred lines
revealed resistance only to RDM. It was also revealed that the SDM-resistant inbreds are invariably resistant to RDM, while
the RDM-resistant inbreds might show differential responses to the SDM. The maize inbred lines identified in this study with
broad-spectrum resistance to downy mildews could be potentially useful for basic and applied research work on downy mildews
in tropical Asia.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
10.
Chloroplast DNA variation in 96 Prunus avium L. cultivars was assessed and compared with the results of a previous study of cpDNA diversity in 23 wild populations of the species. The polymerase chain reaction‐restriction fragment length polymorphism method was used in these studies. Approximately 9% of the chloroplast genome was analyzed, using five universal primer pairs and three restriction enzymes. Ten polymorphic fragments were common to both the wild and sweet cherry; eight polymorphic fragments were found only in the wild cherry. In the cultivars, all mutations were small (5‐30 bp) indels. In the wild populations, a point mutation was also detected in addition to indels. The mutational combinations revealed three haplotypes in the cultivars, which are the main haplotypes in the wild cherry populations. Chloroplast DNA diversity in wild cherry is higher (16 haplotypes) than in sweet cherry cultivars (three haplotypes). The probable wild origin of the sweet cherry cultivars in the maternal line, on the basis of haplotypic similarity, was discussed. 相似文献