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1.
为筛选最适合芽菜培养的小豆品种,以‘白红8号’为试材,设置3种生长调节物质(乙酰水杨酸、乙烯利和6-苄氨基腺嘌呤(6-BA))的各6个浓度(0.0、0.1、0.2、0.3、0.4、0.5 mmol/L;0、20、30、40、50、60 mg/L和0、2、3、4、5、6 mg/L)喷施处理,测定其生物特性(上胚轴长度、上胚轴直径、萌发率、鲜重、干重和产出比)、营养成分(可溶性蛋白和可溶性糖)及抗氧化等特性。结果表明:3种生长调节物质喷施处理都能够提升其营养价值,在乙烯利喷施浓度为50 mg/L,‘白红8号’小豆芽苗菜中各营养成分、酶活性及抗氧化性等均可达到最大值,显著提高了其营养价值。因此,为提高生产中小豆芽苗菜的产量和营养价值,最终确定乙烯利喷施浓度为50 mg/L效果最佳。  相似文献   
2.
为了探寻影响油茶高接换冠后枯桩的相关因素,为今后油茶高接换冠技术改良提供理论依据,调查研究了嫁接方法、接穗品种、砧木粗度、留截高度和嫁接方位等因素对油茶高接换冠后枯桩现象的影响。结果表明:5种因素对油茶枯桩程度影响极显著。其中,采用插皮腹接、砧木直径2~6 cm枯桩程度最低;采用‘华硕’和‘湘林XLJ14’其枯桩程度显著低于其它品种;留截高度越低枯桩程度越低;嫁接方位在外侧枯桩程度最低。偏相关分析结果表明,留截高度对油茶枯桩程度的影响最大;其次是嫁接方法、砧木直径和嫁接品种;而嫁接方位对油茶枯桩程度的影响最小。  相似文献   
3.
Two methyl anthranilate formulations, ReJex‐iT® TP‐40 and AG‐36, were tested as bird‐repelling agents for animal feed and vegetable sprouts, respectively. Feral pigeons (Columba livia) and house sparrows (Passer domesticus) are important pests of animal husbandry and field crops in Israel. In each 4‐day experiment, four birds were held together in an aviary, and were offered four trays or dishes with animal feed or cauliflower sprouts in four corners of the cage. The trays and dishes were transposed daily in a Latin square sequence. Pigeons consumed significantly more untreated feed than treated feed. When no alternative untreated food was offered, there was no significant repellency. Treatment of animal feed with TP‐40 to give 2.0 ml methyl anthranilate kg?1 or less had no repellent effect on sparrows. Concentrations of 4.0 ml kg?1 or more repelled the sparrows significantly. When no untreated feed was presented, pigeons and sparrows preferred the lowest concentration of methyl anthranilate presented. When AG‐36 was tested on vegetable sprouts, the sparrows tended significantly to avoid the highest concentration used—14.5 ml methyl anthranilate litre?1 spray. The inter‐specific differences between the birds indicate that the efficacy of methyl anthranilate formulations as a repellent has to be specified for every species. This study did not determine (1) the possibility of developing habituation, (2) the behaviour of birds under natural conditions in the field, or (3) the influence of the feeding behaviour of a sympatric bird species on the repellency of methyl anthranilate to other species. © 2001 Society of Chemical Industry  相似文献   
4.
A greenhouse screening method for resistance to ringspot (Mycosphaerella brassicicola) inBrassica oleracea is described. High infection levels were achieved by spraying young plants by mycelial inoculum enriched with 3% sucrose. The screening method was tested on three Brussels sprouts, three cabbage and three cauliflower cultivars, with known reactions to ringspot in the field. Resistance was expressed both in cotyledons and true leaves by a lower number of lesions than the susceptible control and/or by hypersensitive reactions. Results of the seedling tests reflected differences in resistance in the field. Under controlled conditions the new test can be applied year-round to young plants, thus accelerating selection procedures.  相似文献   
5.
The comparison of the histologic healing and bronchopleural fistula (BPF) complications encountered with three different BS closure techniques (manual suture, stapler and manual suture plus tissue flab) after pneumonectomy in dogs was investigated for a one-month period. The dogs were separated into two groups: group I (GI) (n = 9) and group II (GII) (n = 9). Right and left pneumonectomies were performed on the animals in GI and GII, respectively. Each group was further divided into three subgroups according to BS closure technique: subgroup I (SGI) (n = 3), manual suture; subgroup II (SGII) (n = 3), stapler; and subgroup III (SGIII) (n = 3), manual suture plus tissue flab. The dogs were sacrificed after one month of observation, and the bronchial stumps were removed for histological examination. The complications observed during a one-month period following pneumonectomy in nine dogs (n = 9) were: BPF (n = 5), peri-operative cardiac arrest (n = 1), post-operative respiratory arrest (n = 1), post-operative cardiac failure (n = 1) and cardio-pulmonary failure (n = 1). Histological healing was classified as complete or incomplete healing. Histological healing and BPF complications in the subgroups were analyzed statistically. There was no significant difference in histological healing between SGI and SGIII (p = 1.00; p > 0.05), nor between SGII and SGIII (p = 1.00; p > 0.05). Similarly, no significant difference was observed between the subgroups in terms of BPF (p = 0.945; p > 0.05). The results of the statistical analysis indicated that manual suture, stapler or manual suture plus tissue flab could be alternative methods for BS closure following pneumonectomy in dogs.  相似文献   
6.
Young trees (4–5 year old) of Betula pubescens Ehrh. growing in a stand in the middle of Sweden (lat. 60°15'N) were cut in early June to stump heights of 0 and 10 cm. The birch stumps were exposed to different relative light intensities (100, 50, 25 and 10%) for 100 days until mid September. Five stumps per treatment were used in a randomized complete block with seven blocks on mesic dwarf‐shrub type with low herbs and three blocks on moist dwarf‐shrub type. The number of sprouting stumps was correlated with relative light intensity and forest type. 2.5 % of the stumps of mesic and 14 % of moist forest type did not produce suckers. On mesic forest type, 7% of the stumps exposed to 10% light did not sprout compared with 1.4, 3.0 and 0% at 25, 50 and 100% light, respectively. At stump height 0 cm fewer sprouting stumps were produced than at 10 cm. The mean height of suckers was significantly lower at 10% light intensity than at other levels. The number of suckers per sprouting stump was not related to light intensity but to forest type. More suckers were produced on mesic than on moist forest type. The dry weight of suckers was significantly lower at 10 and 25% relative light intensity than at 50 and 100%. On moist forest type, the dry weight of suckers was lower than on mesic forest type.  相似文献   
7.
杨树伐根嫁接毛白杨试验研究   总被引:2,自引:0,他引:2  
试验结果表明:不同的白杨派品种对嫁接亲合力的敏感程度不同,敏感性最强的是白杨的741,敏感性最低的是河北毛白杨;选用生长健壮的种条作接穗,伐根生长旺盛,直径在10cm以上,嫁接时间掌握在4月份,且边平茬边嫁接是提高嫁接成活率的主要措施;  相似文献   
8.
刺槐林木生长到中龄林以上阶段,出现老化衰退现象,经人工平茬后达到萌蘖复壮更新的目的,其经营管理技术极为重要。通过清除伐根、严格管护、林间挖沟、补植等系列经营管理技术,才能达到复壮更新的目的。  相似文献   
9.
不同直径伐桩对赤桉萌芽更新影响的初步研究   总被引:4,自引:0,他引:4  
对速生树种赤桉进行了不同直径伐桩(2.1~6cm)萌芽更新影响的研究,结果表明:伐桩的萌芽率及平均萌条数随伐桩直径的增大而增大,萌条直径、高度随伐桩直径变化不大.  相似文献   
10.
The regeneration characteristics of Picea jezoensis Carr. and Abies sachalinensis Masters on cut stumps in natural forest under selection cutting and natural regeneration were studied in a sub-boreal forest of the Hokkaido Tokyo University Forest. The following points were investigated: (1) what decay class of cut stumps are suitable for regeneration of the two conifer species; (2) what part, either a root collar or a cut surface, of a cut stump is suitable for regeneration; and (3) what percentages of cut stumps support conifer seedlings. The percentages of cut stumps that supported conifer seedlings increased as the decay class advanced, but slightly decreased in the latest stage of decay class, V. Both P. jezoensis and A. sachalinensis seedling densities per cut stump and per square meter of cut stumps increased as the decay class advanced. Some root collars in decay class IV supported A. sachalinensis seedlings, but few supported P. jezoensis. Densities of P. jezoensis per cut surface and per square meter of cut surface in decay class IV were higher than those of A. sachalinensis. On the other hand, densities of A. sachalinensis per root collar and per square meter of root collar in decay class IV were higher than those of P. jezoensis. Cut stumps in advanced decay classes are more suitable for regeneration of P. jezoensis and A. sachalinensis than those in early decay classes. Whereas a cut surface is more suitable for regeneration of P. jezoensis, a root collar is more suitable for regeneration of A. sachalinensis. Cut stumps are not sufficient to ensure enough conifer regeneration because not all conifer cut stumps in advanced decay classes support conifer seedlings.  相似文献   
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