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981.
保护地番茄新品种中杂11号的选育 总被引:2,自引:0,他引:2
中杂11号番茄是从欧洲、日本等地引进优良资源材料,经多代复合杂交新育成的适合保护地栽培的中熟杂种一代。抗ToMV、枯萎病、叶霉病。大果型,果实粉红色,果形整齐,耐贮运,商品率高。丰产性好,单位面积产量超过中杂9号。 相似文献
982.
983.
渭北旱塬杨家陇实验分区牧草引种栽培试验研究 总被引:1,自引:0,他引:1
本文根据连续3年的田间试验结果,对引种栽培的20种牧草,从物候期、覆盖度、茎叶比、青干比、生长速度、鲜草产量及抗逆性等七个方面进行对比分析,筛选出了适合渭北旱塬东部地区生态条件的优质高产草种,它们是豆科牧草中的红豆草、沙打旺和草原二号苜蓿等,以及禾本科牧草中的多花黑麦草、苇状羊茅和无芒雀麦等。从而为当地人工种草,强化农牧结合奠定了基础。 相似文献
984.
985.
Oat cultivars (n = 22) varying in origin were examined in laboratory and field tests at Svalöv and Ultuna, Sweden, in 1985 and 1986. Comparisons were made between drought resistance characteristics of juvenile plants and drought responses in yield of crops grown in field. By using automatic, movable rain shelters in combination with drip irrigation systems, both high and low irrigation regimes could be effected in the field experiments.
Black oat cultivars were more stable under water deficiency conditions, particularly on sandy soil. They possessed the highest drought resistance indices both in the laboratory and field. Modern white oat cultivars were found to be most drought sensitive.
Drought resistance index (DRI) and seminal root length (RL), as assessed in seedling stage, were strongly correlated with field drought susceptibility index (S). It is suggested that DRI and RL could be used as selection criteria to increase drought resistance of oats. 相似文献
Black oat cultivars were more stable under water deficiency conditions, particularly on sandy soil. They possessed the highest drought resistance indices both in the laboratory and field. Modern white oat cultivars were found to be most drought sensitive.
Drought resistance index (DRI) and seminal root length (RL), as assessed in seedling stage, were strongly correlated with field drought susceptibility index (S). It is suggested that DRI and RL could be used as selection criteria to increase drought resistance of oats. 相似文献
986.
S. Grzesiak J. Koscielniak W. Filek G. Augustyniak 《Journal of Agronomy and Crop Science》1989,162(4):241-247
The effects of 10-day periods of soil drought during flowering (DI) or pod growth (DII) and during both these phases (DI + DII) on leaf water status, photosynthesis rate, plant growth and production of biomass was studied in pot experiments with field bean. Soil water content during drought spells were kept at 30% of field water capacity. Soil water deficiency DI and DII depressed the leaf water potential relatively to control by about 100 % and 140 % respectively, increased the water deficit by 100 % and 120 % and reduced photosynthesis rate by 80 % and 90 %. Rehydration of tissues completely abolished any decline of photosynthesis rate caused by drought DI, but after drought DII photosynthesis rate remained depressed by about 30 % even after rehydration. Drought periods DI and DII caused more rapid withering of leaves, a decline in the total leaf area and a temporary increase of root weight.
Drought occuring at flowering (DI) also activated the mechanism of plant adaptation to water deficiency during the pod formation phase (DII). Single or double periods of drought had not any significant influence on the number of pods and seeds, but decreased their weight. 相似文献
Drought occuring at flowering (DI) also activated the mechanism of plant adaptation to water deficiency during the pod formation phase (DII). Single or double periods of drought had not any significant influence on the number of pods and seeds, but decreased their weight. 相似文献
987.
本文介绍了在乌鲁木齐旱作栽培条件下,对29份豆科牧草进行3年(1986~1988年)试验后,筛选出具有抗旱、抗寒和丰产等特性的4种类型优良牧草。 1)割草型牧草:有图牧二号紫花苜蓿、图牧一号杂花苜蓿、石河子杂花苜蓿和麦罗斯红豆草。产量高、营养丰富,干草产量9326~10476kg/ha,适宜半干旱地区建立割草场利用。 2)放牧型牧草:有白花野豌豆、草原黄芪和谢家沟岩黄芪。草质好,蛋白质含量高(24~26%),耐牧、再生性好,干草产量3975~5400kg/ha,适宜半干旱地区建立放牧草场利用。 3)防风固沙型牧草:胡枝子和山竹岩黄芪,抗旱性强、青绿期长,干草产量4624.5~4900.5kg/ha,宜在干旱沙漠地区作防风固沙兼牧草用。 4)水土保持型牧草:草藤其茎枝多、生长快、覆盖地面大、产量高,干草产量6750kg/ha,宜在水土流失地区作水土保持及牧草利用。 相似文献
988.
论述了福建省龙岩市发展毛竹丰产林基地的自然优势,以及毛竹丰产林基地的形式与标准,改造现有低产毛竹林的措施,并根据不同的经营目的,论述了材用毛竹林、笋竹两用毛竹林、手工纸用毛竹林的丰产培育措施,毛竹丰产林基地的科学管理,包括机构建立,资料档案建立,竹林结构调整和病虫害防治等。 相似文献
989.
以红灯为试材,探讨了甜樱桃覆草栽培对其开花结实情况的影响。研究发现覆草栽培可有效地提高甜樱桃结果枝叶片数,使叶片营养水平显著提高,平均花芽数量提高1-2个;同时可使红灯樱桃坐果率提高25.04-28.01个百分点。平均单果重增加18%;果汁的可溶性固形物含量增加1.17个百分点,花期滞后3-5d。 相似文献
990.
E Gunnarsson 《Acta veterinaria Scandinavica》1979,20(2):191-199
Isolation of Mycobacterium paratuberculosis from sheep and cattle in Iceland. Acta vet. scand. 1979, 20, 191–199. — Culture experiments concerning the Icelandic variant of Mycobacterium paratuberculosis are described. Various decontaminating agents and culture media were employed and the colonial morphology of freshly isolated strains on different media described. The growth rate and culture requirements are compared with those of the Norwegian goat-pathogenic variant of M. paratuberculosis. For primary isolation modified Herrold’s medium gave the best results. However, on all the various culture media used, the growth of the Icelandic variant was much more sporadic than that of the Norwegian goatpathogenic variant. It is concluded that bacteriological culture is not useful for the diagnosis of Johne’s disease caused by the Icelandic variant of M. paratuberculosis. 相似文献