丁西、丁农、苄甲黄隆防除水稻本田杂草试验示范

1991～1992年我场对浙江省乐清县乐吉化工厂生产的丁西、丁农、苄甲黄隆进行了防除中稻本田杂草药效小区试验和大面积示范。现将情况小结如下。 一、供试药剂 1.5.3％厂西颗粒剂(丁草胺与西草净复配) 2.4％丁农颗粒剂(丁草胺与苄嘧黄隆复配)

4％丁农颗粒剂的应用技术

乐吉化工厂于1990年新开发了丁农颗粒剂除草剂,省农药检定管理所组织全省进行多点试验示范,现将试验结果报告如下: (一)丁农的杀草谱和防效丁农含丁草胺和苄黄隆,丁草胺对稗草高效,苄黄隆对阔叶草、莎草广谱高效,而且对稗草也有较好的抑制效果,二者混配对常见杂草均有高效,但对萍藻类无效。经中国水稻研究所在植物生长箱中试验,亩用丁农750克在25℃、光照强度为8000Lx每日12小时的条件下,对稗和矮慈姑效果均可达100％。 6个单位田间不同用量小区试验,每亩500～2000克对矮慈姑的效果平均在90～99％(表1)。

Control Effect of Four Kinds of Agents for Anthracnose in Autumn Greenhouse Cowpea

In order to mitigate the occurrence and damage of cowpea anthracnose and reduce the chemical pesticide consumption, residue and environmental pollution, the methods of forecasting, randomized block design and statistical analysis were conducted to study the control effect of biopesticide chitosan, biochemical compound Prochloraz-Chitosan and chemical pesticides difenoconazole and thifluzamide by field efficacy trials. The results showed that under serious occurrence of anthracnose in autumn greenhouse cowpea, when the 2% chJtosan AS （2 250 g/hm^2）, 46% Prochloraz-Chitosan EW （450 g/hm^2）, 10% difenoconazole WG （900 g/hm^2, CK） or 24% thifluzamide SC （360 ml/hm^2） were applied three times with an interval of 5-8 d, the control efficiency on day 7, 14 and 20 reached 83%, 78% and 73%, respectively. No significant difference was found in control efficiency among the four kinds of agents. These four kinds of agents, especially chitosan and Prochloraz-Chitosan, could be used as ideal agents for controlling anthracnose, as well as for modern agricultural demonstration zones, pollution-free agricultural products, green agricultural products and organic agricultural products,thereby meeting the develop- ment needs of ＇modern agriculture, green agriculture, organic agriculture and ecological agriculture.

Chinese Plants in the Persian Agricultural Manual Asar va Ahyā’,and a Discussion of Rashīd al-Dīn’s Chinese Knowledge and Agricultural Practice

The Asar va Ahyā’is a manual of agricultural production written in the early fourteenth century by the famous Iranian vizier and scholar Rashīd al-Dīn.Only chapter 6 to chapter 13 of the original work survive,dealing with agriculture and horticulture,and nearly a third of the pages of which are devoted to introducing Chinese plants and related knowledge.In addition to introducing botanical knowledge,the book also covered information on all the aspects of the Yuan dynasty(1271–1368),including the taxation system,monetary system,military system,economy and trade,manufacturing techniques,ethnic customs,food culture,and other fields,providing important materials for research on the dissemination of species,exchange of technologies,communication of ethnic groups,and integration of cultures between China and the world during the thirteenth and fourteenth centuries.Rashīd al-Dīn,the book’s author,took advantage of his identities as a statesman and a businessman to collect rich information about plants all over the world.Motivated by his specific interest in Chinese culture,he included a huge amount of Chinese information in the book.Meanwhile,records in the Asar va Asyā’reflect the author’s practice of researching,planting,and cultivating plants,making the book not only a compilation of agricultural knowledge,but also a report that recorded the author’s agricultural practice.

Probability and Statistical Error of Soil Sampling on Patches Assimilated during Delineation of Precision Farming Management Zones

When precision fanning management zones （MZs） are delineated in an agricultural field for precision nutrient management, unsupervised classification and cluster analysis procedures using remote sensing image analysis software are performed. These unsupervised classification and cluster analysis procedures are performed on the basis of the assumption that grouping of data points into naturally occurring clusters reduces within zone variability. The problem is that, there are small patches of different soil types within each management zone that are regarded as insignificant by the farmer, and are assimilated within larger MZs. These will consequently make soils within a management zone to be inhomogeneous. The objective of this study was to determine the probability of soil sampling occurrences on patches assimilated during delineation of MZs after a cluster analysis was performed. The study was conducted on a 5.0 ha （25°05′34.46″ S and 28°18′30.01″ E） and a 24.4 ha （23°59′04.61″ S and 28°52′29.43″ E） fields in the Waterberg District of the Limpopo Province in South Africa. A bare-soil high resolution Quickbird satellite imagery of a conventionally tilled agricultural field was used to develop MZs in the field. Soils were sampled using systematic unaligned sampling on a 35.0 m and 30.0 m grids for the 24.4 ha and 5.0 ha fields, respectively. Probabilities were calculated based on percentage area assimilated during the cluster analysis procedure that was performed using remote sensing image analysis software. The results indicated that in the 24.4 ha field there were 2.5 ha patches of high and medium zones that were assimilated within the low zone, and thus making low zones non-homogeneous. After cluster analysis and assimilation of patches, the low zone in the 24.4 ha field increased by 45.5% （2.5 ha） while the high zone was 16.4% （2.4 ha） smaller in size. In the smaller field of 5.0 ha, the high zone, which was originally 3.20 ha, lost 0.37 ha （11.6%）, which was assimilated in either low or medium zone. The study indicates that unequal probability proportional to size sampling could be used to minimize error when sampling across precision farming MZs because typically the low, medium and high MZs are not of equal size and do not contribute equally towards the mean values of soil samples.

Agriculture and Technical Cooperation： Nelson Rockefeller and the Work of AIA in Brazil （ 1946-1961 ）

It aims to analyze the work of American International Association for Economic and Social Development （AIA）, a philanthropic agency founded by Nelson Rockefeller, between 1946 and 1961 in Brazil. Aiming to promote better standards of living to the Latin American rural population, AIA is merged in a historical context of increasing US economic and politic influence over Latin America and Brazil, diffusing and adapting US technical assistance programs to local contexts. However, this research developed the idea of an intense process of political negotiation, including resistance from Brazilian political staff. Also, there were many difficulties in adapting these programs to the local context, leading to constant reorganization of the AIA＇s work in Brazil.

Inclusive Development in Latin America and Smallholders＇ Interactive Learning Spaces

Inclusive development appears as a challenge in Latin America countries after the rupture of the social inclusion as a trickle-down effect of the economic growth. Searching development with inclusion, several public policies were implemented in Latin American during the last 10 years focusing on the agri-food production. In order to assess the progress to reach such objectives, two cases are studied. Smallholder milk producers at the Loma Blanca community （Mexico） and smallholders olive producers at Aimogasta （Argentina） were considered. Interactive learning spaces were clearly identified as consequence of the linking among product, producers, and territory. The empirical evidence leaves to see a reflexive attachment between actor and activity in the both studied cases. Differences between dynamics in ILS （Interactive Learning Spaces） of each one of the studied cases were found. Nevertheless, opportunity windows are still opened in order to achieve successful interventions. Why does the small producer continue existing as such？ Why do the small producers remain in small scale rather than creating scale or exiting from the market？ These, and others, are trigger questions through which government and non-government organization can drive their action in the field.

Genetic transformation ofpopulusxeuramericana cv. guariento with chitinase gene

In this paper, populus xeuramericana cv. Guariento was transformed with bean chitinase by Agrobacterium tumefaciens-mediated leaf disc method. Firstly, the leaf explants were pre-cultured at 25℃ for 2d. Secondly, they were infected in Agrobacterium tumefaciens suspension （OD600=0.5） for 20 rain, then were co-cultured for 3d in the dark. Thirdly, the explants were transferred to the selection culture medium （containing Kanamycin 40 mg.L^-1 and Cefotaxime Sodium 800 mg-L1） and incubated at 25℃ until resistance buds formed. Chitinase activity was determined for the positive plants by PCR and PCR-Southern blot hybridization analysis. And, chitinase activity of positive plants was significantly higher than that of control plant, and the highest ratio of activity of NO.4 to that of control was 3.41. It showed that bean chitinase gene had been expressed in the plant genome.