半红树植物水黄皮发芽试验

对水黄皮(Pongamia pinnata)种子去皮沙播、未去皮沙播、去皮泥沙播、未去皮泥沙播四种处理的发芽情况及水黄皮种子发芽临界含水率进行研究。结果表明:去皮有利于显著提高水黄皮种子发芽率和发芽势;去皮泥沙播的发芽率和发芽势均为最优,是宜采用的生产方法;水黄皮种子发芽临界含水率测定表明,种子含水率为14.05%～47.19%时,适宜发芽,发芽率为83.33%～96.67%,含水率为6.97%～11.69%时,发芽率显著下降,为13.33%,低于4.61%时,则停止发芽。     

半红树植物水黄皮幼苗耐盐性的研究

温室内对半红树植物水黄皮幼苗进行7个盐度(5、8、11、14、17、20、23 g.kg-1)的胁迫处理,对各处理下水黄皮生长量、生物量、生理指标和光合速率进行测定,结合10项生长信息指标进行主成分分析。结果表明:水黄皮的苗高增量、地径增量、叶片数增量、根、径、叶干重及总生物量随着盐度的上升均呈下降趋势,在盐度为5和8 g.kg-1的处理下保持较高值,盐度超过11 g.kg-1后骤降;光合速率在盐度为5、8、11 g.kg-1处理下保持较高值,最大值出现在盐度为8 g.kg-1的处理下;SOD活性、游离脯氨酸、质膜透性和丙二醛均有随盐度增大而呈上升趋势;在盐度为5、8 g.kg-1处理下主成分得分较高,水黄皮较适生长,盐度超过11 g.kg-1后不适生长。     

水黄皮苗期生长特性和育苗技术研究

为增加沿海造林树种,丰富沿海防护林种质资源,引进台湾防护林树种水黄皮种子并在惠安赤湖林场苗圃育苗。通过对水黄皮物候和苗期生长特性的观测,研究了水黄皮苗木年生长规律和生长期,结果表明:水黄皮播种后,苗木高、径生长过程表现为慢—快—慢的节律;6—10月为高、径的快速生长期,生长量分别为全年生长量的34%和50.74%。同时提出了水黄皮的育苗技术。     

4种杀菌剂对香蕉叶斑病的田间防治效果

选用42%戊唑·百菌清悬浮剂、25%吡唑醚菌酯乳油、20%烯肟·戊唑醇悬浮剂和48%苯甲·嘧菌酯悬浮剂共4种新型及复配型杀菌剂,对香蕉叶斑病(香蕉褐缘灰斑病、香蕉灰纹病和香蕉煤纹病)进行田间防治效果试验。结果表明,新型杀菌剂25%吡唑醚菌酯乳油对3种叶斑病的防效均表现最好,4次施药后15 d的防效为55.12%~70.10%;其次是42%戊唑·百菌清悬浮剂,48%苯甲·嘧菌酯悬浮剂和20%烯肟·戊唑醇悬浮剂的防效相对较差,不推荐使用。     

水黄皮的引种栽培技术试验

水黄皮(Pongamia pinnata(L.)Merr.),别名水流豆、九重吹、臭腥子、鸟树,蝶形花科常绿乔木,原产于广东和南海、广西、台湾,印度、日本、马来西亚、新几内亚、波利尼西亚群岛、澳大利亚、马斯卡群岛等地也有分布。本树种树冠开阔,枝叶密茂,树姿优美,洁雅,     

乱砍滥伐林木的成因及防止对策

近年来,一些单位和个人受经济利益的驱使,乱砍滥伐林木案件时有发生,尤其是在木材价格回升,木材经营放开以后,发案率明显提高,致使森林植被遭到破坏、林政资源管理工作面临严重威胁。因此在当前和今后相当长一段时间内,加强林木采伐和流通渠道的管理,有效地保护森林资源,仍然是各级林业主管部门和森林公安机关的重要任务。[第一段]     

林木种衣剂适宜杀虫剂、杀菌剂及用量的研究

通对林木种衣剂适宜杀虫剂、杀菌剂及其用量的试验,选择出吡虫啉作为林木种衣剂中的杀虫剂,浓度为1％～3％的吡虫啉对樟子松、兴安落叶松、红皮云杉、沙棘等林木种子的发芽率无显著影响,2％的浓度较适宜;选用恶霉灵与五氯硝基苯组合,可有效防除土壤中引致苗木立枯病的主要致病菌——丝核菌、腐霉菌和镰刀菌。恶霉灵的浓度应控制在7％以内;浓度为5％～30％的五氯硝基苯对林木种子的发芽率无显著影响,可根据种衣剂的其他理化指标确定其用量。     

浅析林区建筑物墙体裂缝的产生及防止

本文阐述了林区建筑物墙体裂缝产生的重要原因有温度、地基、材料等;在设计施工中应采取具体措施。     

枣锈病菌的室内抑菌试验及杀菌剂筛选

在实验室用含药培养基法观测21种杀菌剂对枣锈病病原菌的抑制作用。蓝代、银果、世杰、竹醋酸、库力班、使百克、甲基托布津、叶冠秀8种杀菌剂对枣锈病病原菌的抑制作用最好,必备对菌丝也具有较强的抑制效果。     

植物组织培养中污染产生的原因及防止措施

污染是植物组织培养中的常见问题,给科研和生产造成了不同程度的损失,影响了科研和生产的发展。如何采取有效措施防止污染,把污染降到最低是当前需要解决的问题。该文对植物组织培养中污染发生的原因和防止措施进行了论述。     

The severity and cause of leaf spot disease of Pongamia pinnata L. and fungicidal control of the pathogen

A survey on the symptom and severity of the leaf spot disease of Pongamia pinnata L. was conducted in the nurseries of the Institute of Forestry and Environmental Sciences, University of Chittagong （IFESCU）, Bangladesh Forest Research Institute （BFRI） and Aronnak Nursery in Chittagong. The highest infection percentage and disease index were found in IFESCU nursery, followed by BFRI and the lowest was recorded in Aronnak nursery. The associated organism of leaf spot disease of P. pinnata was isolated from the diseased plant parts and the pathogenicity was established with the isolated fungus. Colletorichum gloeosprioides Penz was proved to be pathogenic. The inhibition of mycelial growth of C. gloeosporioides was observed and identified as suitable fungicides （Bavistin, Cupravite and Dithane M-45） and doses （0.05, 0.10, 0.50, 1.00, 1.50 and 2.00）. The lowest and highest mycelial growth were respectively found on Bavistin and on Cupravite at the concentration of 0.05 after 8th day of incubation. It indicates that out of the three tested fungicides, Bavistin showed most effective, followed by Diathane M-45, and Cupravite was ineffective for its very little inhibition on mycelial growth.     

Genetic variability and divergence studies in pod and seed traits of Pongamia pinnata （L.） Pierre., accessions in Bay Islands

In this study, we assessed the variability in pod, seed traits and oil content of 24 accessions of Pongamia pinnata collected from different parts of the Andaman and Nicobar Islands, India. The experiment was conducted at the Central Agricultural Research Institute, Port Blair during 2010 to 2011. The variability studies for pod and seed traits revealed that, the accession CPT-6 collected from New Wandoor in South Andaman recorded the maximum values for eight traits viz. pod length （75.51 mm）, pod width （34.62 mm）, pod thickness （17.55 mm）, 100 pod weight （770.33 g）, seed width （21.23 mm）, 100 seed weight （377.00 g）, oil percentage （43.92%） and germination percentage （94.7%）. However, the maximum seed length （26.46 mm） was recorded from CPT 2 and the maximum pod-seed ratio was obtained from CPT 13 and CPT 4 （2.50 and 2.44 respectively）. The phenotypic and genotypic coefficients of variations were also close to each other for all traits, but the 100 pod and seed weight exhibited higher phenotypic and genotypic coefficient of variation than the other traits. Estimates of broad sense heritability ranged from 0.30 （for seed length） to 0.95 （pod length） and genetic ad- vance as percent of the mean ranged between 11.66% and 57.40% with seed length giving the lowest value and 100 pod weight giving the high- est value. Both the phenotypic and genotypic correlation between pod length, pod width, pod thickness, 100 pod weight, seed width and 100 seed weight and between pod thickness, 100 pod weight, seed width, 100 seed weight and germination percentage were found to be strong. On the basis of non hierarchical Euclidian cluster analysis, 24 accessions were grouped into six clusters. The maximum numbers of seven accessions were included in cluster VI. The maximum intra cluster distance （10.238）shown by cluster VI and the maximum inter cluster distance （17.021） between V and HI followed by III and II （15.942）. Among the six clus- ters formed the cluster III recorded maximum oil percentage, 100 pod weight, 100 seed ,weight, pod length, pod thickness, pod width, seed width and. germination percentage, while cluster V recorded maximum pod seed ratio and germination percentage. The present findings suggest that the crossing between accessions of cluster V and cluster III will result in a wide spectrum of variability in subsequent generations.     

糖槭叶枯病发病规律及防治

糖槭叶枯病 Phyllosticta negundinis病菌孢子放散开始期和高峰期与每年的温、湿度变化有关。病害发生严重程度与降雨量关系密切 ,降雨早且量大时病害严重。病菌以分生孢子器和分生孢子在病叶上越冬 ,通过气流传播成为翌年初侵染源。喷洒 70 %甲基托布津可湿性粉剂 10 0 0倍液和 75%百菌清可湿性粉剂 80 0倍液均能收到较好的效果     

盆栽柿树角斑病的综合防治技术

通过对盆栽柿树角斑病的病菌初侵染、再侵染过程及发病高峰期的观察 ,分析其发生的最适温湿度等环境条件 ,找出其在我园发生的主要原因及综合防治技术     

Identification and pathogenicity of Alternaria alternata causing leaf spot and blight disease of Ailanthus excelsa in India

Alternaria leaf spot of Ailanthus excelsa is generally considered as minor disease in India. Recently, severe disease outbreaks were recorded in the nursery of the Forest Research Institute, Dehradun, progeny trial at Jhumpa, Haryana, and in a nearby farm field. Leaf symptoms included small circular, brown, necrotic spots with a chlorotic halo. With severe infections, leaf spots coalesced and resulted in leaf blight. A small‐spored Alternaria with concatenated conidia was isolated consistently from the leaf samples with spot symptoms. Sequence analyses of the internal transcribed spacer (ITS) region of ribosomal DNA (rDNA) and the translation elongation factor 1‐alpha (tef‐1α) gene region of two fungal isolates confirmed the species as A. alternata. In detached leaf assays, both isolates produced symptoms similar to those observed on the nursery/field‐grown plants. To validate the detached leaf assay result, pathogenicity was also demonstrated on whole plants in a glasshouse. Koch's postulates were fulfilled by re‐isolating A. alternata from the inoculated leaves. This work is the first to confirm that A. alternata is associated with leaf spot and blight disease of A. excelsa in India.     

荒漠化土地的发生及整治对策

通过对洮南市荒漠化土地发生原因的分析，提出了整治荒漠化的对策；调整产品结构，合理载畜量、乔、灌、草结合，合理开发资源；提高当地群众的认识程度，全民齐动手整治。     

氮、磷、钾对银杏叶黄酮含量与营养生长的效应

通过正交试验，利用营养液盆栽法研究了N，P，K3种大量元素对银杏叶黄酮含量和营养生长的影响。结果表明，处理间叶黄酮含量差异极显著，3种元素对黄酮含量效应大小依次为N，K，P。营养液中N，K，P的质量浓度分别为0．21，0．18，0．7g/L对提高叶黄酮含量的效果最优。银杏新梢的增粗生长，3种元素不同配比间存在极显著差异；N，P对新梢粗生长的主效明显，营养液中N和P的质量浓度以0．28g/L和0．12g/L对新梢粗生长效果最好。     

红檵木花叶病毒病——Ⅱ.发病原因及其防治对策

红檵木采穗母树、砧木、接穗带毒是引发红檵木花叶病毒病的根本原因,苗木生产、盆景制作、园林应用中的反复修剪和蚜虫危害加速了该病的传播和流行.加快红檵木无毒苗木繁育体系的建设、及时清除病株、切断病毒的传播途径、加强病虫防治是防治该病的有效措施.     

The emergence of beech leaf disease in Ohio: Probing the plant microbiome in search of the cause

American beech (Fagus grandifolia) is the target of a newly emerging disease in North America called beech leaf disease (BLD) that affects and disfigures leaves and which can lead to tree mortality. Beech leaf disease may be caused by a newly recognized subspecies of the anguinid nematode Litylenchus crenatae subsp. mccannii, but the associations of this nematode with bacterial and fungal taxa are unknown. We examined microbial communities associated with beech leaves affected by BLD in a 16‐year‐old American beech plantation using molecular methods. We detected L. crenatae subsp. mccannii in anywhere from 45% to 90% of leaves depending on the degree of visual BLD symptoms. Approximately 37% of asymptomatic leaves contained L. crenatae subsp. mccannii, whereas 90% of buds associated with symptomatic leaves contained L. crenatae subsp. mccannii. We found that fungal communities on leaves and buds were unaffected by BLD, but bud and leaves had significantly different fungal communities. Bacterial communities on buds also were unaffected by BLD, but bacterial communities were significantly different between symptomatic and asymptomatic leaves suggesting that the nematode could be altering the community of bacteria on the leaves. Clone libraries indicate that Wolbachia, an intracellular endosymbiont of arthropods, was found only on symptomatic leaves and buds associated with either symptomatic or asymptomatic leaves. In addition, only symptomatic leaves contained taxa in the genus Mucilaginibacter, which previous studies suggest could produce exopolysaccharides. These bacterial taxa could represent a marker for the vector of L. crenatae subsp. mccannii that enables spread between trees and a possible endosymbiont that could facilitate nematode feeding and establishment on nematode infested leaves. Our results are the first to examine changes to the leaf microbiome of this newly emerging pest and may aid identification of mechanisms associated with the spread and success of L. crenatae subsp. mccanni.