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61.
The roots of 20 days old seedlings of tomato (Lycopersicon esculentum Mill.) at the time of their transplantation, were dipped in 10−8, 10−7, 10−6 or 10−5 M of 28-homobrassinolide (HBR) for 15, 30 or 45 min and were allowed to grow in earthen pots, in a net house. The leaves of the plants, at days 30 and 60, possessed elevated quantities of nitrate reductase (NR), carbonic anhydrase (CA) and the contents of chlorophyll. The values for all the above characteristics were significantly higher than that of the water-fed control. The fruits borned at the treated plants were more in number and possessed a lower quantity of ascorbic acid than the control. Moreover, the fruits at ripening, had higher levels of lycopene and β-carotene. Among the treatments, 15 min feeding of 10−8 M HBR proved best. 相似文献
62.
Swarnkar CP Sanyal PK Singh D Khan FA Bhagwan PS 《Veterinary research communications》1998,22(8):545-551
The pharmacokinetics of albendazole was studied in sheep following single oral and intraruminal administration at nematocidal dose rates. The disposition curves of its metabolites indicated increased uptake of the drug in sheep following intraruminal as compared to oral dosing (p<0.05). The increased bioavailability of benzimidazole anthelmintics given by the intraruminal route could be exploited for optimizing the use of anthelmintic for sustained parasite control in small ruminants. 相似文献
63.
Two field experiments were conducted during] 994-95 to study the effect of spray of 10−5 M GA3 at 40 days after sowing on mustard ( Brassica juncea (L.) Czern & Coss.) cv. Varuna grown with basally applied 0, 40, 80 and 120 kg N ha−1 (Expt. 1) and 0,15, 30 and 45 kg P ha−1 (Expt. 2) on pod number per plant, seeds per pod, 1000 seed weight, seed yield, biological yield, harvest index and fatty acid composition of oil. No significant difference between water and GA3 spray was found when basally applied nitrogen was 0 or 40 kg N ha−1 . N80 proved to be the best for yield characteristics. In another experiment on phosphorus, GA3 and 30 kg P ha−1 individually enhanced the yield, but interaction of GA3 and P remained non-significant. The fatty acid composition of oil in both experiments was significantly affected only by nitrogen and phosphorus treatments for oleic acid and erucic acid. It was found that return in the form of yield was more for every kg applied fertilizer under GA, spray treatment. The response was more for N fertilizer in comparison to P. GA3 at a low level of fertilization significantly increased the return from fertilization. 相似文献
64.
M. Farooq T. Aziz M. Hussain H. Rehman K. Jabran & M. B. Khan 《Journal of Agronomy and Crop Science》2008,194(2):152-160
Plant growth and development is hampered by various environmental stresses including chilling. We investigated the possibility of improving chilling tolerance in hybrid maize by glycinebetaine (GB) seed treatments. Maize hybrid (Hycorn 8288) seeds were soaked in 50, 100 and 150 mg l?1 (p.p.m.) aerated solution of GB for 24 h and were dried back. Treated and untreated seeds were sown at 27 °C (optimal temperature) and at 15 °C (chilling stress) under controlled conditions. Germination and seedling growth was significantly hindered under chilling stress. Moreover, chilling stress significantly reduced the starch metabolism and relative water contents (RWC), and increased the membrane electrolyte leakage. However, activities of antioxidants (catalase, superoxide dismutase and ascorbate peroxidase) were increased under stress conditions. Seed treatments with GB improved the germination rate, root and shoot length, seedling fresh and dry weights, leaf and root scores, RWC, soluble sugars, α‐amylase activity and antioxidants significantly compared with untreated seeds under optimal and stress conditions. Induction of chilling tolerance was attributed to maintenance of high tissue water contents, reduced membrane electrolyte leakage, and higher antioxidant activities and carbohydrate metabolism. Seed treatment with 100 mg l?1 GB was the best treatment for improving the performance of hybrid maize under normal and stress conditions compared with control and other levels used. 相似文献
65.
辣椒(Capsicum spp.)原产于中南美洲,大约450~500年前,由葡萄牙商人引入印度,并很快在印度大量栽培,成为印度的重要经济作物。2003年印度辣椒种植面积94.55万hm^2,年产鲜椒450万t。印度是辣椒生产大国,也是世界上种植pimento红辣椒最大的国家,面积和产量分别占全球市场份额的46%和44%,单产4.7t/hm^2,低于中围(25.6/hm^2)、 相似文献
66.
Abdul Qayyum Siddiqui Yousef S. Al-Hafedh Ahmed H. Al-Harbi Seikh A. Ali 《Journal of the World Aquaculture Society》1997,28(1):106-112
Abstract This study was conducted to evaluate the effects of stocking density and monosex culture on growth, survival, yield and feed conversion ratio of freshwater prawn Macrobrachium rosenbergii in concrete tanks. Juvenile prawns with an average weight of 1.8 g were stocked into triplicate tanks at densities of 5, 10, 15 and 20 prawns/m2 , grown for 168 d and fed a 34% tilapia diet. Stocking density had significant effect on prawns. Final mean body weight decreased with the increasing density, being highest at 5 prawns/m2 (29.6 9). and lowest at 20 prawns/m2 (17.4 g). Total yield increased from 135 g/m2 (1,350 kg/ha) at a density of 5 prawns/m2 to 261 g/m2 (2,610 kg/ha) at density 15/mz to 245 g/m2 (2,450 kg/ha) at 20/mz . Feed conversion ratios were high and ranged from 3.7 (5 prawns/m2 ) to 5.6 (20 prawns/m2 ).
In monosex culture of freshwater prawns stocked in triplicate tanks at a density of 5 prawns/m2 for 112 d, the all-male population had the best growth performance and feed conversion ratio, followed by the mixed-sex and all-female populations. The all-male population had 99% marketable prawns (>20 g) with an average yield of 159 g/m2 (1,590 kg/ha); the mixed-sex population had 90% marketable prawns and the yield was 135 g/mz (1,350 kg/ha); and the all-female population had 75% marketable prawns with an average yield of 108 g/m2 (1,080 kgha). 相似文献
In monosex culture of freshwater prawns stocked in triplicate tanks at a density of 5 prawns/m
67.
68.
A. R. Khan A. K. Ghorai R. C. Srivastava S. R. Singh 《Journal of Agronomy and Crop Science》1997,178(2):73-78
Intensive use of chemical herbicides and pesticides has raised serious concern about their effect on non-target organisms, plants, human bodies and the environment. Hence there is a continuous search for benign, harmless, non-hazardous and eco-friendly technology to control the growth of weeds which compete with crops for water, nutrients, light and space; thus reducing crop yield significantly. An attempt was made to control the weeds through smothering. This controls the weeds by cutting off light from the photosynthetic portion of weed plants by using black polyethylene sheets (LPDE film) which inhibit the top growth. Experiments to control the weeds in a lowland rice field through smothering were conducted in the high rainfall coastal region of eastern India wth eight treatments including smothering and conventional methods like hand/mechanical weeding and herbicides, etc. The treatment of smothering for one week + puddling + transplanting proved to be better than other conventional methods and may replace herbicide and hand/mechanical weeding totally with a better rice yield. 相似文献
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