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1.
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   
2.
1. Two experiments were carried out in which fertile, White Leghorn eggs were individually subjected to atmospheric ammonia, for 24 h before incubation, in order to examine the effects on embryo development. 2. In experiment 1, development was unaffected by 0.35 mg/l (493 microliters/l) atmospheric ammonia and slightly reduced by 0.7 mg/l (986 microliters/l) while 7 mg/l (9,860 microliters/l) produced 100% mortality. In experiment 2, embryo development was unaffected by 0.35 mg/l atmospheric ammonia, but severely reduced by 3.15 mg/l (4,437 microliters/l).  相似文献   
3.
1. Broiler chicks fed on a diet containing 500 g/kg expeller copra cake of high residual oil content not only retained less dry matter and gained less weight than those fed on a control diet with no copra, they also experienced difficulty in achieving similar food intakes. 2. Chicks given the 500 g/kg copra ration initially displayed an excited behaviour pattern, which may have developed out of frustration as they could neither derive adequate nourishment from their food nor increase food intakes sufficiently to allow them to achieve their genetic potential for growth. 3. Chicks however showed considerable adaptation in that efficiency of food utilisation and intakes were increased gradually; the latter appeared to be partly regulated by an increased intake of water that was associated with copra feeding. The surface area of the intestines was also increased in order to facilitate the absorption of nutrients, and greater proportions of the nutrients absorbed were converted into body weight. 4. There were no significant differences in 7-week body weights of chicks fed the control, 125 g/kg and 250 g/kg copra diets. Although weight gains at the 500 g/kg inclusion rate were lower, the carcases of these chicks had less abdominal fat and were consequently leaner.  相似文献   
4.
An outdoor growth trial was conducted for 75 days to investigate the effect of C:N ratio and bamboo substrate (S) in brackish water shrimp culture. Penaeus monodon juveniles (0.35 ± 0.03 g) were stocked in experimental tanks with and without bamboo substrate. C:N ratio of 10 and 20 was manipulated with shrimp feed containing 32 % crude protein and rice flour as carbohydrate source. Addition of substrate and higher C:N ratio (CN20+S) significantly reduced (p < 0.01) inorganic nitrogen NH3–N by 48.2 %, NO3–N by 41.6 %, NO2–N by 42.7 % compared with CN10. Substrate addition significantly (p < 0.05) reduced the turbidity by 22.4 % (CN10+S against CN10) and 20.7 % (CN20+S against CN20). Periphyton biomass and total heterotrophic bacterial load were significantly higher (p < 0.05) in CN20+S in comparison with CN10+S treatment. The autotrophic index increased from 123.4 ± 0.62 to 158.9 ± 3.8 for CN10+S and, 121.8 ± 1.6 to 228 ± 9.11 for CN20+S system. Provision of substrate and carbohydrate addition resulted in the highest body weight, 4.87 ± 0.12 g in CN20+S against 3.66 ± 0.07 g in CN20 and 2.90 ± 0.12 g in CN10 through provision of natural food in the form of periphytic algae and heterotrophic bacterial community. Treatment with substrates showed a higher survival rate by 7 % in comparison with without substrate treatments as it acted as shelter to shrimp during molting and there by reduced cannibalism. Thus, our results demonstrated that high C:N ratio and substrate addition improved growth, reduced FCR and better water quality conditions.  相似文献   
5.
The climatic data for 17 years from 1988 to 2004 of the rainfed hill plateaus of Kandhamal district of Orissa (India) were analyzed to find out the monthly climatic index from the calculated values of effective rainfall and evapotranspiration. The 80% dependable monthly climatic index was correlated with crop coefficient and suitable cropping period and sequences for the study area were suggested based on it. The extent of investment, net return and soil loss from agriculture were estimated as per the present condition and for the suggested cropping patterns. A mathematical model was formulated for optimal allocation of area to different crop sequences with different objectives viz. minimization of soil loss, minimization of investment and maximization of net return from agriculture and was solved using linear goal programming technique. The model suggested to take up food crops in area of 1,30,777 ha and perennial grass cover in 3223 ha with a cropping intensity of 1.61 resulting in a net return of Rs 1064.775 millions sustaining soil loss to a tune of 9489.67 thousand tons per year. The model was found to be favourable in respect of higher net return of Rs 8862.34 and lesser soil loss of 23.41 tons/ha than the corresponding present values. But more investment of Rs 4489.01 per ha was required to fulfill the objectives.  相似文献   
6.
1. Unpeeled tubers from 2 high‐protein varieties of sweet potato (white‐fleshed Bosbok, and orange‐fleshed Carmel) were chipped and oven‐dried at 40, 60, or 80°C, to examine the effects on nutritive value. The dried ground chips were substituted for maize at 500 g/kg and the diets fed to day‐old, Ross‐1 broiler chicks for 3 weeks.

2. Compared with Carmel, Bosbok had a lower crude protein content (90 v. 138 g/kg DM) and trypsin inhibitor activity (TIA) (3 v. 5 mg of trypsin inhibited per g flour). Processing did not significantly affect TIA, but the lysine and cystine contents were lowered and the starch content raised as the drying temperature increased. However, whereas this was reflected in increased reducing sugars in Carmel, there was no trend in Bosbok.

3. The results of in vitro pancreatin digestibility and total dietary fibre assays showed variety and processing temperature to be significant factors influencing the nutritive value of sweet potato tubers, with a variety X temperature interaction also being indicated. The interaction was also observed for weight gain, dry matter intake, water: food intake ratios, excreta water content, presence of bile in excreta and liver weights. The best growth was obtained with Bosbok dried at 60°C, for which liveweights at 21 d were 11% lower than for the maize controls.  相似文献   

7.
Transition proteins (TNPs) are essential in chromatin condensation during spermiogenesis, and hence, they are the candidate genes for identifying sperm motility markers. Coding and in silico predicted promoter regions of these genes were investigated in crossbred and purebred cattle, and also, their mRNA quantification was done to explore its use as a diagnostic tool of infertility. PCR‐SSCP analysis revealed two band patterns in fragment III of TNP1 and fragment II of TNP2 gene. Sequence analysis revealed a deletion of “G” nucleotide in 3′UTR region of TNP1 and C>T SNP in intronic region of TNP2 gene. Least square analysis of variance did not reveal any significant influence of nucleotide deletion on any sperm motility parameters in both crossbred and purebred cattle. However, C>T SNP had a significant effect on initial progressive motility (p < 0.05) in purebred cattle and post‐thaw motility in overall cattle population. RT‐qPCR analysis did not reveal any significant variation in TNP1 and TNP2 gene expression among poorly motile and good quality spermatozoa of Vrindavani bulls.  相似文献   
8.
Progesterone (P4) plays a key role in the establishment and maintenance of pregnancy in most mammals. Unravelling the expression of progesterone‐regulated genes can expand the understanding of the embryonic mortality. Accordingly, we studied the relative mRNA expression of the P4‐regulated genes in the buffalo. Uteri were collected from the abattoir and categorized into nonpregnant late luteal phase, stage I (28–38th days of gestation) and stage II (48–56th days of gestation) of pregnancy (n = 6/group). After extraction of total RNA from the endometrial tissues, we carried out qRT‐PCR for determining the relative mRNA expression of the P4‐regulated genes using nonpregnant late luteal phase as calibrator group. The expression of LGALS3BP (essential for maternal recognition of pregnancy) gene was found to be significantly upregulated (p < 0.05), while MUC1 (important for embryo attachment) gene was downregulated in stage I and II of pregnancy. We observed no significant change in the expression of LGALS1, LGALS9 and CTSL genes. The SLC5A11 and SLC2A1 genes (involved in the transport of glucose to endometrium) in early pregnancy were upregulated in the pregnancy stage I (p < 0.05) relative to nonpregnant late luteal phase. The CST3 gene was significantly upregulated in pregnancy stage II (p < 0.01). These results provide molecular insights into the specific pathways involved in foeto‐maternal communication during early pregnancy in buffaloes.  相似文献   
9.
In this study, diffuse reflectance spectroscopy (DRS) approach was examined for making input recommendations in the smallholder cocoa farms of Papua New Guinea (PNG). Soil samples were collected from four provinces of PNG. Soil samples from four different depths (0–10, 10–30, 30–60 and 60–90 cm) of 32 profiles in each of these site were used to create a database of soil chemical and physical properties. Spectral reflectance values at 1 nm interval covering visible to shortwave‐infrared (350–2,500 nm) were collected for each of these soil samples to develop partial least squares regression models. Soil textural fractions, soil organic carbon contents and available N were well predicted by the DRS approach with R2 values larger than 0.75. Moderate to poor estimation efficiencies were observed for remaining parameters. Nevertheless, the estimated soil attributes and their corresponding measured soil parameters were used as inputs to an input recommendation model of soil diagnosis to create input recommendation for a targeted cocoa yield of 1,000 kg dry cocoa beans ha‐1 Resulting input recommendations were similar for both of these input sources (measured and DRS‐estimated) suggesting that the DRS approach may provide an easy way to create input recommendations.  相似文献   
10.
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