The Directional Breeding and Feasibility of Functional Bamboos

The functional bamboos are defined as the ones artificially selected, cultivated and produced in the special functions. Based on the principles to broaden market and maximize benefits, the directional cultivation of the functional bamboos has effectively been used bio-techniques and directionally to breed and cultivate bamboo cultivars to meet human＇s needs. The functional bamboos should feature stability, excellent quality and convenient production as well as easy duplication. The functional bamboo cultivars should also enhance the scientization, standardization industrialization and mass production. Given no negative environmental impact, ou purpose is to select, cultivate and develop one or more functional bamboos cultivars to meet the consumers＇ material and spiritual needs and bring more economic ben efits for the producers. The authors believe that directionally breeding functiona bamboo cultivars is not only feasible in techniques, resources and policies, but also in economy and market development. This implicates great significance for the green economic development given the features of China＇s natural resources.

Chinese yam(Dioscorea opposita Thunb.) Notillage Ecological Cultivation Technique

For traditional cultivation of Chinese yam, it is necessary to dig a deep trench duringsowing and harvest, wasting labor and time, and Chinese yam requires good quality of cultivated land, causing serious impact on the development of yam industry due to the competition with food production. Yam no-tillage ecological cul- ture techniques, combined with advantage of yam directional tuberization, could en- able the cultivation of yam inlow-production field, barren hills and sloping field, forest land and other non-staple food land and thus could promote farmers＇ income as well as improving the ecological environment.

Vertically Band-based Orientation Cultivation for Dioscorea opposita

The author made innovation on cultivation technology of Dioscorea oppo- site based on orientation tuberization. According to large furrow, big tuber, and lots of soils, a tuber bed is established suitable for yam growth, and a vertically band- based orientation is introduced. Specifically, soils are ground and colored bands are paved in bottom of furrows where tubers can be cultivated. At harvest, band soils can be removed to collect tubers. It is simple and easy. The yield can be as high as 75 000 kg/hm2. It is applicable in a variety of lands, especially for arid areas, mountains areas or under-forest lands with slopes from 10°to 25°. Semi-mechanical or mechanical planting and harvest can be applied with promising prospects.

Effect of Main Cultivation Factors on Oil Quality and Stability of Brassica napus Hybrids

[Objective] This study aimed to analyze the influence of five cultivation factors： sowing date, plant density, nitrogen fertilizer amount, phosphate fertilizer amount and potash fertilizer amount on oil quality and stability of Brassica napus hybrids. [Method] Statistical analysis was carried out based on the data from previous studies and our work. [Result] Sowing date had no significant influence on oil quality and stability of B. napus hybrids. The plant density shared a positive correlation with 18-C fatty acid （FA） content, unsaturated fatty acid （UFA） content, total content of linoleic acid and linolenic acid, index of unsaturated fatty acid （IUFA）, so a large plant density can improve the oil quality （by increasing18-C FA content, UFA content, total content of linoleic acid and linolenic acid）, but reduce the oil stability （by increasing IUFA）. The amount of nitrogen fertilizer had no significant influence on the contents of 18-C FA and UFA, but significant positive correlations with the total content of linoleic acid and linolenic acid and IUFA. So, the total content of linoleic acid and linolenic acid can be reduced by increasing nitrogen amount, meanwhile the oil stability was also decreased. Phosphate fertilizer amount did not affect 18-C FA significantly, but was negatively correlated with the UFA content, total content of linoleic acid and linolenic acid, and IUFA. So, increasing the amount of applied phosphate fertilizer can reduce UFA content, total content of linoleic acid and linolenic acid, thereby improving oil stability. Potash fertilizer had no significant influence on the IUFA, a significant positive correlation with 18-C FA content, an insignificant positive correlation with the the UFA content, and a negative correlation with the total content of linoleic acid and linolenic acid. The oil content of rapeseed shared an extremely significant positive correlation with 18-C FA content and UFA content, an negative correlation with the total content of linoleic acid and linolenic acid, and no significant correlation with IUFA. [Conclusion] This study identified the effects of five main cultivation factors on oil quality and stability of B. napus hybrids, and the correlations of oil content with 18-C FA content, UFA content, total content of linoleic acid and linolenic acid, and IUFA.

Effect of Cultivation on Soil Organic Matter and Aggregate Stability

Agricultural sustainability relates directly to maintaining or enhancing soil quality. Soil quality studies in Canada during the 1980 s showed that loss of soil organic matter (SOM) and soil aggregate stability was standard features of non-sustainable land management in agroecosystems. In this study total soil organic carbon (SOC), particulate organic matter (POM), POM-C as a percentage of total SOC, and aggregate stability were determined for three cultivated fields and three adjacent grassland fields to a…

A Way to Decrease the Negative Impact of Aquaculture on other Marine Inhabitants

Spat collectors deployed at sea, in addition to the target species, attract also many larvae of accompanying species, which die after transplanting the cultivated one into cages. However, these juveniles often have a higher value than the cultivated species, and their mortality is caused by smaller sizes. These are： red king crab, Japanese sea cucumber, sea urchins, Japanese cucumaria and several species of ascidians and sponges. However, the use of a realized niche, rather than a fundamental one, in selecting the area and depth to install collectors, and also improvement of their design, make it possible to cultivate a target species without reseeding to other constructions. This not only facilitates the cultivation process, but also increases the survival rate of the cultivated and accompanying species, since at the bottom, they reach either marketable or viable size in comfortable conditions.

The Current Status, Problems and Prospects of Researches on the Carrying Capacities of Ecological Environment in China

Determining the carrying capacity of ecological resources is the key to finding contradictions between human activities and the environment,as well as the links between economic growth,environmental protection and social development.In recent years,the carrying capacity of the ecological environment has been extensively studied at home and abroad.Through extensive literature research and analysis,this paper discusses the current status and main problems of recent research on the carrying capacity of the ecological environment in China.For example,two of the main problems are that:1)the concepts and connotations are not clear enough,and 2)the research content is not systematic enough.This is followed by a summary of the evaluation index system and main calculation methods.Finally,according to the research status and development trends at home and abroad,the possible direction for the development of this research field in the future is proposed.

Identification of Colletotrichum spp. isolated from strawberry in Zhejiang Province and Shanghai City,China

Strawberry anthracnose, caused by Colletotrichum spp., is a major disease of cultivated strawberry. This study identifies 31 isolates of Colletotrichum spp. which cause strawberry anthracnose in Zhejiang Province and Shanghai City, China. Eleven isolates were identified as C. acutatum, 10 as C. gloeosporioides and 10 as C. fragariae based on morphological characteristics, phylogenetic and sequence analyses. Species-specific polymerase chain reaction （PCR） and enzyme digestion further confirmed the identification of the Colletotrichum spp., demonstrating that these three species are currently the causal agents of strawberry anthracnose in the studied regions. Based on analysis of rDNA internal transcribed spacers （ITS） sequences, sequences of all C. acutatum were identical, and little genetic variability was observed between C. fragariae and C. gloeosporioides. However, the conservative nature of the Mvnl specific site from isolates of C. gloeosporioides was confirmed, and this site could be used to differentiate C. gloeosporioides from C. fragariae.

Population-level performance of Arabidopsis thaliana (L.) Heynh in dense monocultures

Aims Very little is known about the performance of non-agricultural plant species in monocultures,even though nearly all agricultural species have experienced the transition from multi-species environments to dense monospecific stands during the breeding process.In the light of recent work that highlighted the possibility that the weedy species Arabidopsis thaliana can offer novel insight into crop breeding,we aimed to test the effect of sowing density on group and individual performance in different photoperiod environments in A.thaliana.Methods We studied the performance of A.thaliana Cvi-0 ecotype.The choice of Cvi-0 was based on a preliminary experiment in which plants of Cvi-0 ecotype exhibited high competitive performance.Sowing densities used were 17.6,8.8,4.4,2.2 and 1.1 cm^(2) per plant and photoperiod environments 12 or 16 h of day light.Important Findings In this experiment,populations attained constant total seed yield for all densities.Some interaction effect occurred,as at high sowing density and at longer day length plants produced heavier seeds,whereas at shorter day length seed weight was negatively related to plant density.These results shed light on different strategies that annual plants can adopt when they face intense intraspecific competition,and could help to offer new perspectives for breeding crops with enhanced group performance.