Research Progress in Formation and Detection Method of Dextran in Sugarcane Production

Dextran in sugarcane production process is formed by Leuconostoc rnesenteroides. The content levels of dextran is related to sugarcane varieties, field condition （planting pattern, temperature, humidity, sunlight, soil, foreign material）, de- gree of injury （refractory cane, harvesting methods）, and can be rapidly and accu- rately measured by Dextran Immunonephelometric Test Kit. The presence of dextran indicates that sucrose has been lost, so sugarcane dextran is a direct and reliable indicator to measure sugarcane freshness and quality.

Mechanization technology:The key to sugarcane production in China

Sugarcane is an important cash crop in southern China now planted on about 1.5 million ha in the main production areas in Guangxi,Zhuang Autonomous Region and Yunnan,Guangdong,and Hainan Provinces.Since the cost of labor in China is increasing rapidly and the price of local sugar is uncompetitive with the product from mechanized international producers,China needs to change its sugarcane production methods from manual work to mechanization in order to catch up with international trends in this global industry.Although a lot of effort in China have gone into sugarcane mechanization since the 1960s,the overall level of mechanization in sugarcane production is still only approximately 30%,which is about 20%lower than that achieved in the other main field crops.Almost all of the sugarcane grown in China is still harvested by hand.In order to summarize past experience and promote the mechanization of sugarcane production in China,this paper reviews the whole process of developing mechanization since 1960s and describes the current state of sugarcane mechanization in China.The research currently being undertaken and the main obstacles to be overcome in developing a mechanized sugarcane production system,are described.The design and testing of sugarcane harvesting machinery and its key components has been a significant research area by some Chinese universities,research institutes,and manufacturing companies in these past decades.This paper reviews that research and outlines the main achievements which have been made in this area.Mechanized harvesting systems for sugarcane,and the appropriate harvesting patterns suitable for different growing conditions applying in China,have also been studied.The paper concludes with some comments on the future directions for progress in China’s mechanization of sugarcane production and some policy suggestions to facilitate the industry's transition.

Impeded Acidification of Acid Sulfate Soils in an Intensively Drained Sugarcane Land

Recent research results suggest that acidification of acid sulfate soils may be inhibited in well-drained estuarine floodplains in eastern Australia by the absence of natural creek levees. The lack of natural levees has allowed the inundation of the land by regular tidal flooding prior to the construction of flood mitigation work. Such physiographical conditions prevent the development of pre-drainage pyrite-derived soil acidifica- non that possibly occurred at many levee-protected sites in eastern Australian estuarine floodplains during extremely dry spells. Pre-drainage acidification is considered as an important condition for accumulation of soluble Fe and consequently, the creation of favourable environments for catalysed pyrite oxidation. Under current intensively drained conditions, the acid materials produced by ongoing pyrite oxidation can be rapidly removed from soil pore water by lateral leaching and acid buffering, resulting in low concentrations of soluble Fe in the Pyretic layer, which could reduce the rate of pyrite oxidation.