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61.
Field experiments during two successive rainy seasons were conducted in southern Vietnam to evaluate the effects of a commercial inoculant biofertilizer (‘BioGro’) and fused magnesium phosphate (FMP) fertilizer on yield and nitrogen (N) and phosphorus (P) nutrition of rice. Inoculation with BioGro containing a pseudomonad, two bacilli and a soil yeast significantly increased grain yield in the second season and straw yield in both seasons by 3–5%. The FMP fertilizer significantly increased grain yield from 1.72–2.33 t ha?1 to 2.99–3.58 t ha?1 along with total N and P accumulation at all rates in both cropping seasons. In the first season the difference in grain yield between BioGro treated and untreated plots was marginal but in the second season BioGro out-yielded the control at all the rates of added P. Overall, BioGro application did not compensate for low P fertilizer application to the same extent previously demonstrated for low N fertilizer applications.  相似文献   
62.
Water, Air, &; Soil Pollution - High applications of P fertilizers and manure are general practice in intensive agriculture and may cause eutrophication in adjacent streams. Bioavailability of P...  相似文献   
63.
Five anionic polyelectrolytes were prepared with different molar ratios of acrylamide and acrylic acid monomers. The optimum flocculation conditions were found to depend on the polyelectrolyte and characteristics of the sample. The optimum time for flash mixing for alum and for polyelectrolytes was 1 to 2 min. The optimum flocculation time was 10 to 25 min and optimum flocculation intensity varied between 20 to 30 rpm. The pH was found to be inversely proportional to flocculation efficiency. The COD removal and coliform bacteria removal were 65 and 98%, respectively.  相似文献   
64.

Background

Rice aleurone layer develops different colours with various chemical tests that may help to develop some rapid tests for identification/grouping of rice varieties. Understanding the colour inheritance pattern could enable to develop chemical clues that may help for genetic purity analysis along with grow-out-test.

Results

In this study, inheritance pattern of aleurone layer colour was studied in parents, F1 and F2 progenies derived from the crosses IR 36 × Acc. No. 2693 and IR 64 × Acc. No. 2693. The parent IR 36 showed light yellow (NaOH/KOH) and brown (phenol/modified phenol test) colour; whereas, Acc. No. 2693 revealed wine red/dark wine red (NaOH/KOH) and light brown colour/no reaction (phenol/modified phenol test). In contrary, another parent IR 64 exhibited light yellow (KOH/NaOH) and dark brown (phenol, modified phenol) colour. Both the F1 showed an intermediate light wine red colour (NaOH/KOH) and dark brown (phenol and modified phenol) colour, which is dominant over their one of the parents. The colour pattern with standard phenol/modified phenol, NaOH and KOH tests in F2 progenies of both the crosses showed 9:7 (complementary gene interaction) and 11:5 ratios (reciprocal dominance modification of recessive alleles), respectively.

Conclusions

Our findings clearly elucidate the colour inheritance pattern in rice that may facilitate to develop rapid chemical tests to identify/ group the varieties for genetic purity analysis.
  相似文献   
65.
In the uplands of Eastern Himalayan Region (EHR) of India, dry-seeded rain-fed rice occupies considerable area. However, productivity of rice in this region is very low and is mainly due to frequent occurrence of intermittent soil moisture stress, weed infestation, and poor crop establishment. Keeping this in view, a field experiment on rain-fed direct-seeded rice was conducted during two consecutive years 2011 and 2012 at the EHR of India (27° 95′N latitude and 94° 76′E longitude, 662 m above MSL) to evaluate the effect of seed priming (SP) with different durations (0, 12, 18, and 24 h) and in situ furrows at various row intervals as moisture conservation measures (MCM) on seed germination, plant stand, profile moisture recharge, rice productivity, water and energy use efficiency, and harvest monetary benefits. Results revealed that SP for 24 h duration significantly (p < 0.05) improved the seed germination and crop stand, rice grain yield by 30–36 %, water use efficiency by 29–36 %, and energy productivity by 15–22 %. In situ furrows at regular and alternate row intervals also registered 1.89–3.2-fold increase in profile moisture recharge, 20–34 % higher rice productivity, 23–33 % improvement in water use efficiency, and 6–16 % increase in energy productivity over without MCM. Seed priming helped in improving seed germination, seedling establishment, and plant stand, while MCM was useful in mid-season rainfall capture and profile moisture recharge during intermittent moisture stress for better plant growth. However, adoption of in situ furrows (regular and alternate row intervals) as MCM increased the cost of cultivation by 13–27 % over normal practices but was compensated by the significant increase in grain yield, water use efficiency, benefit:cost ratios, and farmers’ profit.  相似文献   
66.
In India, cotton crop residues available after cotton picking are considered as waste materials and disposed off the field. For developing better residue management practices, knowledge of the decomposition kinetics is needed. Short-term laboratory incubations were conducted to determine the pattern of C mineralization from cotton leaves and stems [stem pieces (ca. 2 cm) vs. ground stem (0.25 mm)] in the two major soil groups (vertisols and inceptisols) on which cotton is grown to a large extent. The amount of C mineralized was significantly greater from leaf- (18.3% of added C) and ground stem-C (19% of added C) when compared to stem pieces-C (13.2% of added C). Differences between the residues were not seen in the inceptisols. The cumulative amount of C mineralized ranged from 9.6-11.5% of the added C. Narrowing the C:N ratio of stem did not enhance C mineralization.  相似文献   
67.
Conflicts over the management of common pool resources are not simply material. They also depend on the perceptions of the protagonists. Policy to improve management often assumes that problems are self-evident, but in fact careful and transparent consideration of the ways different stakeholders understand management problems is essential to effective dialogue.  相似文献   
68.
A reexamination of the crop water stress index   总被引:18,自引:0,他引:18  
Summary Hand-held infrared radiometers, developed during the past decade, have extended the measurement of plant canopy temperatures from individual leaves to entire plant canopies. Canopy temperatures are determined by the water status of the plants and by ambient meteorological conditions. The crop water stress index (CWSI) combines these factors and yields a measure of plant water stress. Two forms of the index have been proposed, an empirical approach as reported by Idso et al. (1981), and a theoretical approach reported by Jackson et al. (1981). Because it is simple and requires only three variables to be measured, the empirical approach has received much attention in the literature. It has, however received some criticism concerning its inability to account for temperature changes due to radiation and windspeed. The theoretical method is more complicated in that it requires these two additional variables to be measured, and the evaluation of an aerodynamic resistance, but it will account for differences in radiation and windspeed. This report reexamines the theoretical approach and proposes a method for estimating an aerodynamic resistance applicable to a plant canopy. A brief history of plant temperature measurements is given and the theoretical basis for the CWSI reviewed.  相似文献   
69.
Intergeneric hybrids involving a wild crucifer, Diplotaxis siifolia (2n = 20; DsDs), and two crop Brassica species, namely Brassica rapa (2n = 20; AA) and B. juncea (2n = 36; AABB), were developed through sequential ovary/ovule culture. Hybridization was successful only when D. siifolia was used as the female parent, indicating unilateral cross incompatibility. Hybrids were intermediate between the parents for morphological characteristics but had low male as well as female fertility. Meiotic studies of hybrids revealed partial homoeology between Ds and A/B genomes.  相似文献   
70.
Eighty-eight long, slender, scented Basmati rice germplasms were collected from North India during an exploration mission. Morpho-agronomic characterisation of the accessions revealed a significant variability in leaf length, culm length, culm number and panicle length.  相似文献   
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