Cereal grains are the most important food source for humans. As the global population continues to grow exponentially, the need for the enhanced yield and minimal loss of agricultural crops, mainly cereal grains, is increasing. In general, harvested grains are stored for specific time periods to guarantee their continuous supply throughout the year. During storage, economic losses due to reduction in quality and quantity of grains can become very significant. Grain loss is usually the result of its deterioration due to fungal contamination that can occur from preharvest to postharvest stages. The deleterious fungi can be classified based on predominance at different stages of crop growth and harvest that are affected by environmental factors such as water activity (a(w)) and eco-physiological requirements. These fungi include species such as those belonging to the genera Aspergillus and Penicillium that can produce mycotoxins harmful to animals and humans. The grain type and condition, environment, and biological factors can also influence the occurrence and predominance of mycotoxigenic fungi in stored grains. The main environmental factors influencing grain fungi and mycotoxins are temperature and a(w). This review discusses the effects of temperature and a(w) on fungal growth and mycotoxin production in stored grains. The focus is on the occurrence and optimum and minimum growth requirements for grain fungi and mycotoxin production. The environmental influence on aflatoxin production and hypothesized mechanisms of its molecular suppression in response to environmental changes are also discussed. In addition, the use of controlled or modified atmosphere as an environmentally safe alternative to harmful agricultural chemicals is discussed and recommended future research issues are highlighted.
Aflatoxins ; Agrochemicals ; Animals ; Aspergillus ; Atmosphere ; Biological Factors ; Crops, Agricultural ; Edible Grain ; Fungi* ; Humans ; Mycotoxins ; Penicillium ; Water*

This paper is aimed to study the differences of allelopathic effects of Panax notoginseng under different allelopathic chemicals resources and selection of appropriate rotation crops. The additive main effects and multiplicative interaction ( AMMI) model had been used to evaluate the stability of allelopathic effects of P. notoginseng on the varieties of corn, wheat and rice properly. The model could use not only to evaluate the stability of non-regional trial data but also explore the interaction between the rotation crop genotypes and donor substances more efficiently. Meanwhile, correspondence analysis can be used in the AMMI to evaluate genotype stability and donor substances. Ejingza No. 1 (g6) had stronger allelopathic effects with high stability, but Yunrui No. 1 (g9) which was appropriate rotation crop genotype, had weaker allelopathic effects with high stability. These findings will aid in choosing appropriate rotation crops and establishing proper rotation system.
Allelopathy ; Crops, Agricultural ; Panax notoginseng ; chemistry

This paper summarizes the studies on improving crop nutritional quality including protein, saccharide and lipid through gene engineering in recent 10 years. Special emphasis is laid upon the improvement of protein contains and amino acid components. The food safety caused probably by gene engineering and some ways to solve the problem are introduced briefly.
Crops, Agricultural ; Genetic Engineering ; Nutritional Physiological Phenomena

One approach to apply precision agriculture to optimize crop production and environmental quality is identifying management zones. In this paper, the variables of soil electrical conductivity (EC) data, cotton yield data and normalized difference vegetation index (NDVI) data in an about 15 ha field in a coastal saline land were selected as data resources, and their spatial variabilities were firstly analyzed and spatial distribution maps constructed with geostatistics technique. Then fuzzy c-means clustering algorithm was used to define management zones, fuzzy performance index (FPI) and normalized classification entropy (NCE) were used to determine the optimal cluster numbers. Finally one-way variance analysis was performed on 224 georeferenced soil and yield sampling points to assess how well the defined management zones reflected the soil properties and productivity level. The results reveal that the optimal number of management zones for the present study area was 3 and the defined management zones provided a better description of soil properties and yield variation. Statistical analyses indicate significant differences between the chemical properties of soil samples and crop yield in each management zone, and management zone 3 presented the highest nutrient level and potential crop productivity, whereas management zone 1 the lowest. Based on these findings, we conclude that fuzzy c-means clustering approach can be used to delineate management zones by using the given three variables in the coastal saline soils, and the defined management zones form an objective basis for targeting soil samples for nutrient analysis and development of site-specific application strategies.
Cluster Analysis ; Crops, Agricultural ; Electric Conductivity ; Soil

Field experiments were conducted in farmers' rice fields in 2001 and 2002 to study the effects of nitrogen (N) management strategies on N use efficiency in recovery (RE), agronomy (AE) and physiology (PE) and redistribution of dry matter accumulation (DMA) and nitrogen accumulation (NA) in two typical rice cultivars in Jinhua, Zhejiang Province. This study aimed mainly at identifying the possible causes of poor fertilizer N use efficiency (NUE) of rice in Zhejiang by comparing farmers' fertilizer practice (FFP) with advanced site-specific nutrient management (SSNM) and real-time N management (RTNM). The results showed that compared to FFP, SSNM and RTNM reduced DMA and NA before panicle initiation and increased DMA and NA at post-flowering. There is no significant difference between SSNM and FFP in post-flowering dry matter redistribution (post-DMR) and post-flowering nitrogen redistribution (post-NR). These results suggest that high input rate of fertilizer N and improper fertilizer N timing are the main factors causing low NUE of irrigated rice in the farmer's routine practice of Zhejiang. With SSNM, about 15% of the current total N input in direct-seeding early rice and 45% in single rice could be reduced without yield loss in Zhejiang, China.
Crops, Agricultural ; metabolism ; Fertilizers ; Nitrogen ; metabolism ; Oryza ; metabolism

OBJECTIVETo study optimum planting density and sowing depth of Tulipa edulis.

METHODThe effects of different planting densities, sowing depth and thin plastic film cover were studied on yield, rate of increase, bulb weight increased multiples, and proliferation rate of bulb.

RESULT AND CONCLUSIONUnder 30-200 bulbs per squremeter density range, the yield increased with the density increasing, and reached significance level. In 5-20 centimeter depth range, the yield and the number of harvested bulbs enhanced along with the sowing depth increasing, and the best sowing depth was 20 cm. Thin plastic film cover showed no effect on the growth.

OBJECTIVETo explore effects on allelopathic autotoxicity of Rehmannia glutinosa of different abatement measures.

METHODThe experiments for abating allelopathic effects of R. glutinosa were designed with the reducing rate as a indication, three measures of the treating soil with lime nitrogen, and water washing were employed, R. glutinosa- Achyranthes bidentata rotation system and using Achyranthes bidentata as green manure, and seedling transplant were also studied for the abatement effect.

RESULTEffect of seedling transplant was the best, reducing rate of transplant and bare root transplant on the 20th day after emergence was 76.80%, 71.70%, respectively. The reducing rate of the treating soil with microorganism reached 54.25%. The effects of water washing and R. glutinosa-A. bidentata rotation system and using A. bidentata as green manure were not satisfied. Especially only using A. bidentata as green manure without rotation system worsened the allelopathic effects of R. glutinosa.

CONCLUSIONAll measures can abate allelopathic effects of R. glutinosa to some extent except only using A. bidentata as green manure.

OBJECTIVETo investigate the effects of top pruning on fruiting characters of Platycodon grandiflorum, and find the suitable stage, in which seed growth and development furtherly.

METHODOne-year old seedlings were chosen and planted in field. Plant height, branching number, fruit number per plant, 1000 grains weight were measured during growth and development period, respectively.

RESULTThe treatment of top pruning postponed in turn the flowering date, lowered the plant heights and the fruit number per plant, increased the branching number and influenced significantly on 1000 grains weights.

CONCLUSIONThe suitable stage of top pruning for producing seeds was from June 20th to July 5th.

Apomixis has been widely concerned because of its great potential in heterosis fixation. Artificial apomixis is an important direction of current apomixis research. Mitosis instead of Meiosis (MIME) produces diploid gametes that is identical with the maternal genetic composition and is a key step in the artificial creation of apomixes. This paper reviews the occurrence of MIME and its application in crop apomixis and the problems encountered, in an aim to provide reference for expanding the application of MIME in crop apomixis.
Apomixis ; Crops, Agricultural ; genetics ; Diploidy ; Germ Cells ; Meiosis ; Mitosis

Insecticidal protein genes from Bacillus thuringiensis are currently the most widely used insect-resistant genes. They have been transferred to many crops for breeding and production. Among them, cotton, maize, potato and other insect-resistant crops are commercialized, creating considerable economic benefit. In this review, we summarized advances in identifying functional genes and transgenic crops for insect resistance, compared different strategies for enhancing vigor of insecticidal protein and utilizing gene stacking as well as listing valuable groups of stacked genes. In addition, the methods for multiple gene transformation was discussed.
Animals ; Bacterial Proteins ; genetics ; Crops, Agricultural ; genetics ; Endotoxins ; genetics ; Hemolysin Proteins ; genetics ; Insecta ; Plants, Genetically Modified