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1.
为检验油菜素内酯(BR)的应用效果,采用大田试验的方法,研究不同浓度BR及其配施外源钙对日光温室越冬茬番茄生长、生理特性变化、坐果及产量的影响。结果表明,在试验浓度范围内,高浓度BR处理对番茄前期株高生长起到一定的抑制作用;适宜浓度的BR处理使株高增加。高浓度BR处理使番茄叶片MDA含量显著增高,且降低可溶性糖含量;适宜浓度的BR处理可降低番茄叶片MDA含量和相对电导率,增加番茄叶片的脯氨酸含量和可溶性糖含量,提高番茄的叶绿素含量。高浓度的BR处理会抑制番茄坐果,降低番茄第1花序的产量;适宜浓度的BR处理可提高番茄各层花序的坐果率,提高番茄产量。BR配施外源钙处理对番茄前期生长、生理指标优化、提高番茄坐果率和产量的加成效应不明显。综上,BR配施外源钙处理的效果不显著,适宜浓度的BR可以单独在日光温室越冬茬番茄生产上应用,以提高番茄的抗逆性和产量。 相似文献
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在盆栽条件下研究了VA菌根茵对茄子、黄瓜、籽瓜的侵染、促生和防病作用。结果供试菌均可侵染供试作物,但促生和防病效应具特异性.Glomus.Versiforme和G.mosseae均促进茄子的生长,但只前者减轻了茄子黄萎病。G,sp3促进黄瓜提早开花,但不防病;G.macrocarpum减轻了黄瓜细菌性角斑病的发生,却并无促生作用。G.sp4不但促进籽瓜的生长,而且是短期内减轻籽瓜炭疽病的有效组合。 相似文献
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Abstract. In Australia, stubble burning and tillage are two of the major processes responsible for the decline of soil organic carbon concentration in cropped soils, and the resulting soil degradation. However, the relative importance of these two practices in influencing the soil organic carbon concentration and the long-term impact on soil quality and productivity are not clear. The effects of stubble burning as practised by farmers in southeastern Australia were evaluated in two field trials, one of 19 years duration, the other of 5 years. Conventional tillage (three tillage passes) led to greater loss of soil organic carbon than stubble burning. Loss of total soil organic carbon attributed to stubble burning in the 0–10 cm layer was estimated to be 1.75 t C ha−1 over the period of the 19-year trial, equivalent to 29% of that lost due to tillage. In the 5-year trial, no change in soil organic carbon due to stubble burning was detectable. Changes in soil quality associated with stubble burning detected in the longer trial included a reduction in macro-aggregate stability, and increases in pH and exchangeable K+ . Only the latter two were detected in the shorter trial. A higher mean wheat yield (average 0.15 t ha−1 ) following stubble burning was observed in the 19-year trial but not in the 5-year trial. Research to monitor the longer term effects of stubble burning is needed, and to identify conditions where loss of soil organic carbon is minimized. 相似文献
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节能日光温室光照强度的分布及其变化 总被引:8,自引:0,他引:8
在充分考虑了温室结构和植株生长影响的基础上,对日光温室光照强度的变化规律进行了研究,得到的主要结论如下:冠层上部辐射强度的南北差异比东西差异大;冠层下部光照条件东西差异明显,南北差异不大。总体上讲,辐射强度上下差异比南北差异明显。 相似文献
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外源甜菜碱对作物的抗旱作用效果研究 总被引:9,自引:0,他引:9
通过小麦浸种、水培、大面积喷施和茄子盆栽试验,研究了不同浓度外源甜菜碱对作物的抗旱作用效果。结果表明:外源甜菜碱浓度为25~50mg/L时可促进小麦种子发芽,光合作用强度[达7.07~7.57μmol/(s·m~2)]及生物学产量增加;在外源甜菜碱浓度100 mg/L时小麦幼苗叶片硝酸还原酶活性最高,达到35.23μg/(g·h),同时小麦抗旱性增强。数学模式寻优结果表明:在外源甜菜碱浓度26.4~68.9mg/L,土壤水分含量12.6%~20.7%时,可获得最佳的茄子生物总量。 相似文献
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Kazuhiko Narisawa Hitoshi Kawamata Randolph S. Currah Teruyoshi Hashiba 《European journal of plant pathology / European Foundation for Plant Pathology》2002,108(2):103-109
One hundred and twenty-three fungal isolates were obtained from 225 root segments of eggplants, melon, tomato, strawberry and Chinese cabbage, grown as bait plants in a mixed soil made up of samples from different fields in Shizuoka, Japan. Isolates belonging to Mycelium radicis atrovirens (MRA), including Phialocephala fortinii, were the most prevalent in all the five bait plants. Eleven of the 123 isolates, after being inoculated onto axenically reared eggplant seedlings, almost completely suppressed the pathogenic effects of a post-inoculated, virulent strain of Verticillium dahliae. Seven of these 11 isolates had come from the roots of eggplant and included Heteroconium chaetospira,
P. fortinii, and unidentified species of Fusarium, Penicillium, Trichoderma and MRA. P. fortinii, H. chaetospira, a non-sporulating isolate with white mycelium (SWM) and MRA were easily reisolated from root segments. Hyphae of H. chaetospira, P. fortinii and SWM colonized the root tissues of eggplant without causing apparent pathogenic symptoms. The mechanisms by which these endophytes confer resistance to infection by V. dahliae are unknown but the effectiveness of these fungi in a laboratory setting indicates that they have potential as biocontrol agents and merit further investigation. 相似文献