论林地承包经营权转让的条件

林地承包经营权是一种用益物权。林地承包经营权可以依法转让,但法律对转让方、受让方的身份有一定的限制,并且规定林地承包经营权的转让必须经过发包方的同意,但发包方的同意权在性质上应界定为监督权而非决定权,发包方不同意承包方转让林地承包经营权必须具有法定的理由,避免权力滥用。     

Practical breeding strategies to improve resistance to Septoria tritici blotch of wheat

Septoria tritici blotch (STB), caused by fungal agent Zymoseptoria tritici (previously known as Mycosphaerella graminicola) is a devastative foliar wheat diseases globally. Importance and potential threat of STB have been discussed historically and geographically. This paper reviews information on the Z. tritici—wheat pathosystem and proposes approaches to identify resistance genes and to advance in breeding for STB resistance. Screening of resistant lines/cultivars, QTL mapping analysis within genetic populations derived from crosses, detection of new resistance gene(s) and finally application of Stb gene carrier line/cultivar in crosses are the major stages of a practical wheat-breeding program against STB of wheat. Phenotyping and genotyping outputs on the top of each other should confirm each other, so it needs to expose a resistance gene carrier line/cultivar in the epidemic condition at seedling/adult plant stage to confirm resistance performance of detected gene(s) in the real condition. On the other word, detecting an associated QTL to resistance should not be considered as the end of investigation. Climate change resulted geographical disease pattern conversion where some diseases became more important in some area where they had not been serious in the past and vice versa. Hence, a reconsideration of wheat disease importance zone is necessary to predict regions where STB is and will be a limitation for wheat yield improvement.     

转录激活因子CBF与植物的抗胁迫能力

很多低温相关基因的启动子中都含有CRT/DRE元件,CBF蛋白可以与该元件结合而使这些基因得以表达。拟南芥CBF基因有4种,分别为CBF1、CBF2、CBF3和CBF4。CBF1、CBF2和CBF3基因聚集在拟南芥第4染色体的短臂上,CBF4定位在第5染色体上。CBF2与CBF1、CBF3与CBF1的核苷酸序列具有较高的同源性,分别为81%和84%。CBF2和CBF3的氨基酸序列分别与CBF1大约有84%和86%相似,且表达模式完全相同。CBF4蛋白由224个氨基酸组成,与其他CBF蛋白有63%的同源性。在CBF1、CBF2、CBF3和CBF4转基因拟南芥植株中,不需低温刺激,4种CBF基因的组成表达都能够激活含有CRT/DRE元件的COR基因表达,从而提高植株的抗冻性。自1997年发现CBF1基因以来,已有很多成功导入CBF基因的报道。本文就这4个转录因子的性质及其在植物抗寒、抗旱和耐盐方面的作用进行了阐述。     

马铃薯抗病毒遗传及与产量性状的关系

本文研究了马铃薯对卷叶和花叶病毒抗性的遗传及与产量性状的关系.结果表明,抗病性与群体产量没有显著的遗传相关性,抗病性主要通过保证马铃薯植株的正常生长发育而间接保持群体的高产稳产性能.马铃薯对卷叶病毒抗性、株高、茎粗、有效株率和主要产量性状的遗传主要由亲本的累加基因效应决定,且同一亲本在不同性状上的一般配合力效应差异较大.因此,抗病高产育种中各目标性状的协调选择是十分重要的.群体有效株率和茎粗的选择可使抗病性和丰产性同步提高.马铃薯对花叶病毒的抗性、加性和非加性作用同时存在.群体抗病性、有效株率和产量的遗传进度高,选择潜力大.     

Evaluation of greenhouse inoculation techniques to screen sorghum for resistance to downy mildew

Summary Six inoculation techniques were compared for the artificial promotion of downy mildew (Peronosclerospora sorghi) in sorghum. These were (1) sprouted seeds incubated between sporulating infected leaves, (2) sprouted seeds depped in conidial suspension, (3) sprouted seeds sprayed with conidial suspension, (4) seedlings at plumule stage inoculated with drops of a conidial suspension, (5) seedlings at plumule stage sprayed with a conidial suspension, and (6) seedling showered with conidia falling from infected leaves. Seedlings at the one-leaf stage sprayed with a conidial suspension (6 × 10⁵ ml^-1) showed the highest systemic infection (100%) in the susceptible lines IS 643 and IS 18433. This technique is effective, repeatable, and allows the deposition of a conidial suspension as a fine mist on the entire seedling surface. In the greenhouse, the technique was used to test the downy mildew reaction of genotypes previously reported as resistant (< 5% incidence) in 3–4 years of field screenings. Of the 61 genotypes tested, 21 were free from downy mildew, 14 had less than 5% incidence, and the rest showed variable susceptible reactions. Therefore, the technique can be reliably and effectively used in the greenhouse to detect disease escapes and to indentify resistance.     

水稻白叶枯病成株抗性相关基因的表达谱

采用cDNA-AFLP(amplifiedfragmentlengthpolymorphism)分析了水稻白叶枯病成株抗性相关基因的表达。在检测的16000个基因片段中,122个表现为差异表达。对其中的70个片段进行了克隆和测序,有41个片段编码的氨基酸序列与已知基因同源。通过Northern杂交和RT-PCR分析了29个功能已知基因的表达,检测到10个基因表现出表达差异。这些基因编码蛋白参与电子和质子转运、泛素—蛋白体途径以及表观遗传调控(epigeneticregulation)等。这些基因在不同处理的水稻苗期和成株期叶片中存在表达差异,表明它们可能在成株抗性中发挥重要作用。     

茄子SSR标记在番茄上的通用性分析

微卫星标记(SSR)是分子育种中常用的遗传标记之一,但目前报道的番茄SSR标记并不能满足番茄分子育种的需要,有必要发展出更多的SSR标记,近缘物种转移法是一种发展SSR标记简便快速的方法。本研究分析了茄子SSR标记在番茄上的通用性情况,结果表明:300对茄子SSR引物中有111对能在番茄基因组DNA上扩增出产物,97对引物扩增出的带型在茄子、番茄间相似程度高,标记通用率为32.3%;EST-SSR比基因组SSR的通用性更好,前者通用率为36.6%,后者为30.0%。将这些标记转移到番茄上,能节省开发番茄SSR标记的成本。     

红花草莓红花基因RAPD标记转化为SCAR标记

红花草莓不但具有经济价值,还具有很高的观赏价值。本研究将3个与红花基因连锁的RAPD标记即AW65679（1031bp）、S484（620bp）与S1383（500bp）进行了克隆与核苷酸测序,并根据测序结果设计4对SCAR引物,将这4对引物对红花草莓品种粉红熊猫、白花草莓品种鬼怒甘及它们的杂交后代进行PCR扩增程序优化和鉴定,筛选出一对SCAR引物可扩增出与红花基因连锁的特异片段AW65679（1038bp）,这就是与红花基因连锁的SCAR标记。SCAR标记因其稳定性好,重复性高将为草莓分子育种开辟一条新的有效途径。     

利用POX同工酶测定谷子(粟)品种对黑穗病的抗性

采用箱栽方法种植 12个抗病性不同的谷子品种 ,分析了芽苗过氧化物酶 (POX)活性及同工酶的变化。结果证明 ,对黑穗病免疫的品种接菌后POX活性平均提高 2 2 8%。越是易感病的品种接菌后POX活性提高得越多。感病品种平均提高 71 6 % ,高感品种平均提高 95 0 %。同工酶酶谱 ,免疫品种接菌后不变 ,越是易感病的品种接菌后酶谱变化越大。二维排序 ,免疫品种接菌与不接菌的两个点落在同一点上或附近 ,d值平均为 3 1。易感病品种的两点相去甚远 ,其中 ,感病品种平均d值 12 2 ;高感品种平均d值 13 2。采用芽苗POX同工酶测定谷子品种抗黑穗病性 ,简便快速     

Response of cotton genotypes to water and heat stress: from field to genes

Cotton is a crop of tropical and subtropical regions but the seed cotton yield is highly influenced by abiotic stresses like drought and heat. Response of cotton genome to abiotic stresses is highly complex and involve many genes. A comprehensive study, involving cotton genotypes developed through conventional and synthetic tetraploid method, was designed to (i) study the introgression of heat and water stress tolerance by using wild relatives (ii) evaluate genetic markers for marker assisted selection against water and heat stress. Two separate experiments for water and heat stress tolerance with a common control were established. Treatments in each experiment include a control and a stress treatment. Heat stress was applied by sowing crop two month earlier than the control treatment, whereas water stress was imposed by withholding alternate irrigation. Analyses of variance depicted highly significant (P ≤ 0.01) effect of genotypes and both stresses on boll retention, boll weight and seed cotton yield. Interaction of genotypes with stress in both experiments was also highly significant (P ≤ 0.01). Genotypes derived from interspecific crosses performed consistently in stress conditions compared to control which prove it a reliable method to introgress stress related genes from wild parents. Four genes reported for water stress tolerance and five genes reported for heat stress tolerance were evaluated by field results for efficient marker assisted selection (MAS). Results verified drought stress genes but heat stress genes could not explain genetic variability caused by heat stress. It is concluded from the results that separate genes may be responsible for heat stress tolerance for vegetative and reproductive stages, therefore, selection criteria should include both the traits.     

Application of Wavelet Transform to De-noising Method

The wavelet transform is a new subject developed quickly in the past ten years. Compared with the Fourier transform, the wavelet transform is a part of time-frequency transform. The most important character is that it can be used to transform a signal into basic units at different scales and location, each unit represents a component of original signal difference from others. The wavelet transform has been proven to be a powerful and efficient tool for processing signal due to this character. This paper introduces the de-noising principles of the wavelet transform. It is proved to be an effective method by the simulating analysis.     

Rpest—An indicator linked to a crop model to assess the dynamics of the risk of pesticide water pollution: Application to banana-based cropping systems

Like many intensive monocultures, some features of banana-based cropping systems may be detrimental to the environment. Pesticide use is a major cause of surface water and groundwater pollution. The risk of water pollution due to pesticides is very high in the insular areas of the French West Indies (FWI). In order to assess these risks and help design more sustainable cropping systems, we propose using an indicator to assess the risk of pesticide pollution over time (Rpest). Rpest provides dynamic assessments through a linkage with a cropping system model that simulates environmental factors and agricultural practices. An expert validation check was conducted and demonstrated that Rpest can rank cropping systems by risk as well as experts. A sensitivity analysis highlighted that the indicator can take the properties of active ingredients and pedoclimatic data into account in assessments. Rpest helps to pinpoint high pollution risk periods. It can also be used to test alternatives and compare systems. This tool can be integrated into a model-based, global, prototyping methodology used for more sustainable cropping systems.     

薄荷茎叶比施肥技术体系初探

不同施肥水平与种植密度是影响薄荷生物学性状,即单株主茎叶片数、分枝数、分枝叶片数及有效叶片数的重要因素,其中分枝叶片数影响较大,可用单株分枝叶片数与主茎叶片数之间的比值反映出影响程度大小。因此,可以通过不同密度茎叶比测定,了解田间土壤肥力水平,作为施肥的重要依据,再结合施肥试验及多年生产实践,求出薄荷茎叶比、茎叶比施肥系数及施肥量公式,从而探讨了薄荷茎叶比施肥技术体系。     

Greenhouse technique to evaluate onion resistance to pink root

Summary An assay for resistance of onion to pink root Pyrenochaeta terrestris was developed, employing infested vermiculite medium with an adequate inoculum concentration of the fungus to minimize escapes of susceptible plants.Plant material other than seed was used. Either root-excised 6–8 week-old seedlings or onion sets were planted in infested vermiculite, and kept for two successive 2-week periods of growth differing in light and temperature regimes. During the first phase a short-day regime of 10 h and 17±1°C was kept, under which a vigorous root system was obtained. For an additional 12–14 days under 26±1°C and 12 h light the prolific roots were then exposed to the optimal temperature for disease development.This technique enables one to distinguish easily between susceptible Allium cepa material and a resistant line of A. fistulosum.Contribution from the Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel. No. 1022-E, 1984 series.     

利用基因芯片检测水稻细菌性条斑病抗性相关基因

细菌性条斑病(简称细条病)是水稻的主要病害之一.为了鉴定细条病的抗性基因,我们利用Affymetrix的基因芯片对抗病品种Acc8558和感病品种H359中受细条病菌侵染调控的基因进行高通量的检测.在两品种中共检测到956个差异表达基因,其中12个基因在两品种中一致上调,54个基因在两品种中一致下调,20个基因在两品种中表达变化方向相反.对差异表达基因的基因本性、代谢路径和启动子进行了分析.比较发现有30个差异表达基因的位置与已报道的控制水稻细条病的QTL吻合.本研究为水稻细条病抗性基因的克隆提供了线索,为揭示水稻细条病抗性的分子遗传机理奠定了基础.     

Addition of Colchicine to Wheat Anther Culture Media to Increase Doubled Haploid Plant Production

Chromosome doubling is critical for obtaining doubled-haploid plants from wheat (Triticum aestivum L.) anther culture. The most common doubling method applies colchicine to the plant. However, colchicine is phytotoxic and can induce a high frequency of plant death. In this experiment, anthers from two wheat genotypes (“Pavon 76” and ‘Centurk’) were placed on nine embryoid initiation media having three sugar sources (maltose, sucrose, and maltose + glucose) with three colchicine concentrations (0.0, 0.1, and 0.2 g · l^-1). Wheat starch was used as a gelling agent. After three days, the anthers were washed and moved to fresh media without colchicine. Increasing the colchicine concentration decreased the number of embryoids produced from 77.4 embryoids/100 anthers to 29.9 embryoids/100 anthers, but did not significantly affect the frequency of plant regeneration (0.49 green plants/embryoid to 0.40 green plants/embryoid), and increased the frequency of doubled-haploid plants (19.0 doubled-haploid plants/100 green plants to 72.3 doubled-haploid plants/100 green plants). Considering the total number of doubled-haploid plants produced, low levels of colchicine added to the initiation media were very effective.     

烟蚜茧蜂繁育及对烟蚜的防治效果探索

653100云南省玉溪市红塔区许家湾路26号（农职院生活区）     

番茄灰霉病菌对几种杀菌剂的敏感性测定

摘 要： 【研究目的】通过研究本地区的番茄灰霉病菌对几种常用药剂的敏感性,筛选出防治效果较好的药剂。【方法】采用菌丝生长速率法和孢子萌发法,测定了两株番茄灰霉病菌对6种杀菌剂的敏感性。【结果】在六种药剂中,乙霉威对两株番茄灰霉病菌的抑制效果最好,多菌灵对番茄灰霉病菌抑制效果最差,两菌株均对多菌灵产生高水平抗性;菌株SY和WS对扑海因分别表现为中抗和高抗;菌株WS对甲基托布津已产生了高水平抗性;腐霉利对灰霉菌孢子的萌发抑制效果明显,而嘧霉胺对抑制菌丝生长的效果明显。【结论】乙霉威在防治番茄灰霉病时可作为首选药剂,生产中应减少甲基托布津和多菌灵的使用次数和剂量并避免单剂使用。     

Relationship of plant height and days to maturity with resistance to spot blotch in wheat

A total of 1,407 spring wheat (T. aestivum) lines of Indian and CIMMYT (International Maize and Wheat Improvement Centre, Mexico) origin were evaluated for plant height, days to maturity and resistance to spot blotch (caused by Bipolaris sorokiniana) during the 1994–95, 1995–96 and 1996–97 crop seasons. The frequency distribution of genotypes, based on disease score ignoring the growth stages, differed from the distribution in which disease score was assessed on a similar growth stage. Two crosses each,between `tall resistant × dwarf susceptible' and `late resistant × early susceptible' genotypes, were made. The evaluation of homozygous resistant lines in the F₃, F₄ and F₅ generations of both crosses showed a wide range of plant height and days to maturity. These lines showed significant differences for plant height and days to maturity but did not show a significant difference for AUDPC values of spot blotch. The correlation coefficients for AUDPC versus plant height or days to maturity were weak, i.e., – 0.336 and 0.061, respectively. Results indicated that resistance to spot blotch severity was independent of plant height and days to maturity in progenies from these crosses.     

Spatial and temporal changes to the water regime of a Mediterranean vineyard due to the adoption of cover cropping

The use of cover cropping is currently increasing in vineyards but its development remains hampered in Mediterranean regions because of the possibility of severe competition for resources. However, recent studies on intercropping in vineyards have shown that in some situations, water stress may not be greater than that prevailing in bare soil vineyards. Over a 4-year period, we studied the effects of introducing a cover crop in terms of temporal and spatial (i.e. row vs. inter-row) changes to the water regime of a Mediterranean vineyard. The experiments compared the water dynamics prevailing under three different treatments: a perennial cover crop, annual cover crop or the use of chemical weed control.A compensatory growth of the grapevine root system was revealed, thus partly prevented direct competition for resources between it and the intercrop. The rooting of a permanent cover crop was deeper than that of an annual crop, with a higher root density. Consequently, the soil compartment dried by the cover crop was larger and the grapevine was forced to explore deeper soil layers. In the presence of a cover crop on the inter-row, the grapevine also concentrated its root system below the row and dried out this soil compartment more intensively. Overall, associating grapevine with a cover crop led to a spatial distinction of soil zones exploited by the two species. The present study provides evidence that this spatial shift mainly resulted from a temporal shift in the dynamics of resource uptake by the associated species. Indeed, cover crops began to take up water before grapevine budbreak and had almost completely dried out the soil compartment they explored before grapevine water uptake became significant. This led the grapevine to modify its rooting and explore other soil zones. This phenomenon is possible in deep soils and limits competition for water between the grapevine and cover crop. Such competition is also reduced because of better soil water replenishment during the winter in the presence of a cover crop. Nevertheless, our experiments showed that this additional water mainly benefited the intercrop and did not totally compensate for transpiration by the grass cover.In conclusion, this work shows how cover cropping can spatially and temporally modify the water regime of a vineyard, and how grapevine can partially adapt to limit water competition under certain conditions. These findings provide a clearer understanding of the water dynamics prevailing in such a system, and an opportunity to model these dynamics.