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61.
杨树嫁接苗生长量与伐根直径及嫁接株数关系的研究 总被引:1,自引:0,他引:1
为了搞清杨树嫁接苗成活率和生长量与伐根直径及嫁接株数的关系 ,对杂交杨伐根嫁接冀秦 1号杨、冀秦 2号杨、冀秦 3号杨、山海关杨、加杨、 1- 2 14杨进行了研究。结果表明 :接穗品种虽不同但同属黑杨派 ,其嫁接在相同伐根上的成活率及胸径生长量均无显著差异 ;在本研究范围内 ,嫁接株数对嫁接苗的生长量产生显著的影响 ,而伐根直径及其交互作用对其影响不显著 ;伐根直径在 15~ 2 5cm时以嫁接 3株为宜 ,在 2 6~ 30cm时可嫁接 4株 相似文献
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Survival of tanoak (Lithocarpus densiflorus) and Pacific madrone (Arbutus menziesii) seedlings was studied in order to interpret succession in conifer hardwood forests and to determine ways to suppress establishment of these species. Seed protected from rodents and birds, and unprotected seed was sown in clearcuts and in conifer stands 40 to 200+ years old. Second-year survival rates of tanoak seedlings were high (50–70%) in exposed clearcuts and conifer stands. Seed predators appear to be of prime importance in limiting tanoak establishment. Survival rates of Pacific madrone seedlings on the same sites as the tanoak were low (0–8%), and many factors caused mortality. Seedlings of both species grew slowly; after 3 years, average tanoak height was only 6.0 to 14.0 cm, average madrone height 2.0 to 6.0 cm. 相似文献
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植物生长物质萘乙酸、吲哚丁酸、生根粉对枣树根蘖苗的促控作用非常明显,其作用是通过对地上部加长生长、加粗生长和地下部根系发育的影响来实现的。三种外源激素的浓度分别为萘乙酸0.1%、吲哚丁酸0.1%、生根粉0.05%,其中尤以萘乙酸0.1%效果最好,成活率可高达71.4%。浓度过高则会抑制根蘖苗的生长,降低成活率。 相似文献
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The value of molecular expression of KIT and KIT ligand analysed using real‐time polymerase chain reaction and immunohistochemistry as a prognostic indicator for canine cutaneous mast cell tumours 下载免费PDF全文
T. A. Costa Casagrande L. M. de Oliveira Barros H. Fukumasu B. Cogliati L. M. Chaible M. L. Z. Dagli J. M. Matera 《Veterinary and comparative oncology》2015,13(1):1-10
This study investigated the correlation between KIT gene expression determined by immunohistochemistry and real‐time polymerase chain reaction (RT‐PCR) and the rate of tumour recurrence and tumour‐related deaths in dogs affected with mast cell tumour (MCT). Kaplan–Meier curves were constructed to compare tumour recurrence and tumour‐related death between patients. The log‐rank test was used to check for significant differences between curves. KIT‐I, KIT‐II and KIT‐III staining patterns were observed in 9 (11.11%), 50 (61.73%) and 22 (27.16%) tumours, respectively. Tumour recurrence rates and tumour‐related deaths were not associated with KIT staining patterns (P = 0278, P > 0.05), KIT (P = 0.289, P > 0.05) or KIT ligand (P = 0.106, P > 0.05) gene expression. Despite the lack of association between KIT staining pattern and patient survival time, the results suggest a correlation between aberrant KIT localization and increased proliferative activity of MCTs. RT‐PCR seems to be a sensible method for quantitative detection of KIT gene expression in canine MCT, although expressions levels are not correlated with prognosis. 相似文献
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