We previously reported on the strong symbiosis of AMF species (Rhizophagus irregularis CD1) with the cotton (Gossypium hirsutum L.) which is grown worldwide. In current study, it was thus investigated in farmland to determine the biological control effect of AMF on phosphorus acquisition and related gene expression regulation, plant growth and development, and a series of agronomic traits associated with yield and fiber quality in cotton. When AMF and cotton were symbiotic, the expression of the specific phosphate transporter family genes and P concentration in the cotton biomass were significantly enhanced. The photosynthesis, growth, boll number per plant and the maturity of the fiber were increased through the symbiosis between cotton and AMF. Statistical analysis showed a highly significant increase in yield for inoculated plots compared with that from the non inoculated controls, with an increase percentage of 28.54%. These findings clearly demonstrate here the benefits of AMF-based inoculation on phosphorus acquisition, growth, seed cotton yield and fiber quality in cotton. Further improvement of these beneficial inoculants on crops will help increase farmers' income all over the world both now and in the future.
Long-term continuous cotton cropping results in a significant decrease in soil quality and soil organic carbon, threatening cotton yield. The application of organic amendments is considered an effective management practice for the sustainability of soil productivity and often increases yield. However, the sustainable improvement in the cotton yield, stability, and soil fertility over time resulting from organic amendments with cotton straw and organic manure still need to be confirmed with research, especially under a continuous cotton cropping system. This study evaluated the effect of 12 years of consecutive application of cotton straw and organic manure on continuous cotton yield, soil quality, and soil organic carbon. Four treatments, i.e., chemical N and P fertilizers (NP, control), NP plus cotton straw (NPS), NP plus manure (NPM), and NP plus cotton straw and manure (NPSM), were carried out. The results indicated that the addition of cotton straw and organic manure improved the temporal stability and sustainability of cotton yield. The combination of cotton straw and organic manure resulted in the greatest improvement, increasing the average annual cotton yield by 32.28% compared with the control (NP). A correlation analysis revealed that cotton yield was closely related to soil quality and soil organic carbon. The application of cotton straw and organic manure increased cotton yield by enhancing soil fertility, especially the quantity and quality of soil organic carbon, which improved the supply and cycling of soil nutrients and benefited the stability and sustainability of the cotton yield. Reusing cotton straw and organic manure could improve the sustainable productivity of cotton soil and provide additional environmental value as well as having great potential for cleaner and sustainable cotton production.
In this study, newly harvested 'New Queen' melons were treated with calcium chloride (CaCl 2 ) and 1-methylcyclopropene (1-MCP) alone or in combination before storage.The results show that respiration rate, ethylene release, activity, and gene expression of pectinases such as polygalacturonase (PG), pectin methylesterase (PME), and pectate lyase (PL) in 'New Queen' melons decreased dramatically when treated with 2% CaCl 2 and/or 1 mL • L -1 1-MCP.In addition, climacteric behavior and flesh hardness reduction were inhibited.It was also discovered that softer melon flesh was more conducive to the growth and reproduction of decay-causing microorganisms, according to their growth curves in melons that were different in flesh hardness, suggesting inhibiting fruit softening can slow down the growth of microorganisms in fruit flesh and thus reduce fruit decay rate.The combined use of CaCl 2 and 1-MCP was more effective in suppressing respiration rate, ethylene release, and protopectin hydrolysis, which could greatly delay the softening, reduce the decay rate, and extend the shelf life of 'New Queen' melons.
The method of division in canopy was used for studying the effect of distribution of relative light intensity in the different tiers of tree canopy on the production and fruit quality of Conference pear cultivar.The results showed that the distribution of relative light intensity in the canopy gradually descended from upper to lower tier.In the same tier,the relative light intensity was increased from inner to outer.Less 30% of the relative light intensity distributed mainly in the lowest tier of canopy.The yield distributed mainly from 1.0 m to 2.5 m height of the canopy.And the fruit mass,flesh firmness,titratable acidity was positively correlated to relative light intensity.The regression equations in relationship between relative light intensity and production and fruit quality was established.The optimum relative light intensity was 67.2% for high yield,56.5% for fruit mass,58.2% for flesh firmness,55.0% for soluble solid content,and 39.7% for titratable acidity,respectively.