Effect Of Temperature And Water On Characteristics Of Physiological And Biochemical And Accumulation Of OYDV And LYSV In Leaves Of Garlic

Garlic(Allium sativum L.) belongs to Liliaceae Allium, is one year or biennial herb plant. Because of its unique food and medicinal value, currently garlic is widely grown around the globe with gradually increase in demand. Garlic cultivation in China has 1,400 years of history and is the world’s major cultivation and production areas. The accumulation of viral diseases in garlic bulbs severely affects the yield and quality resulting from the reproduce by the bulbs. Due to the increasing demand in domestic and international market for yield and quality requirements, many researchers have paid attention to remove the viral diseases by shoot tip culture, heat treatment, bulbils breeding, virus detection, fertilization cultivation, while the study on choice of planting area to improve yield and quality has not been reported at present. Thus, it is an effective way to improve the yield and quality of garlic by selecting suitable planting and breeding environment. In order to reach the aim and provide a theoretical basis and technical reference for the improve the yield and quality, the study on the characteristic of physiology and biochemistry, plasmodesmata structure and gene expression of OYDV and LYSV was conducted under the treatment of temperature and water by detecting the levels of soluble sugar, soluble protein, proline, superoxide dismutase(SOD), photosynthetic parametersetc, etc. And the results are as the follows:1. The content of soluble sugar, soluble protein, proline and activity of SOD were increased by 12.33%、23.75%、7.2% and 25.22%,the content of total chlorophyll,chlorophyll a,chlorophyll b,net photosynthetic rate and stomatal conductance were decreased by 51.2%, 49.1%, 63.03%, 72.26% and 85.2%, intercellular CO2 concentration were increased by 120% in leaves of garlic under the treatment of low temperature 4℃ compared to the control.Under the treatment of high temperature 35℃, The content of soluble sugar, soluble protein, proline and activity of SOD were increased by 27.15% 、 34.99% 、 14.04% and 33.43%,the content of total chlorophyll,chlorophyll a,chlorophyll b,net photosynthetic rate and stomatal conductance were decreased by 65.53%、65.70%、48.13%、92% and 80.1%, intercellular CO2 concentration increased 133% in leaves of garlic compared to the control. The content of soluble sugar, soluble protein, proline and activity of SOD were increased by 11.63%、26.07%、24.89% and 8%,the content of total chlorophyll,chlorophyll a,chlorophyll b,net photosynthetic rate and stomatal conductance were decreased by 51.2%、49.1%、63.03%、72.26% and 85.2%, intercellular CO2 concentration were increased by 108% in leaves of garlic under the treatment of 15% water content compared to the control. Under the treatment of 10% water content, the content of soluble sugar, soluble protein, proline and activity of SOD were increased by 31.05%、32.59%、39.11%、20.65%,the content of total chlorophyll,chlorophyll a,chlorophyllb,net photosynthetic rate and stomatal conductance were decreased by 56.74%、57.23%、67%、75.55% and 87.82%, intercellular CO2 concentration increased 116% in leaves of garlic compared to the control. The result showed that the effects of the treatment of high temperature and 10% water content on physiological and biochemical characteristics on garlic significantly higher than the treatment of low temperature and 15% water treatment. It proves the growth characteristics that garlic likes the growth environment of damp and cold.2. There were also a significant different in the change of plasmodesmata structure under the treatment of temperature and water. Under the treatment of temperature, no verrucous protrusions on both ends of the wire microtubules, while bifurcate appeared, and the number and the size of silk microtubules increased significantly, and the number under 35 ℃ were significant higher than 4 ℃. Under the treatment of water, there were verrucous protrusions on both ends of the wire microtubules, and the size of micro tube increased with the increase of drought stress, and fork silk appeared under the stress of 10% water.3. Under the temperature stress, low temperature 4℃ was not conducive to both of the expression of the OYDV and LYSV genes expression and accumulation, while the gene expression of OYDVwas significantly higher than the control, and LYSV was the opposite under 35℃. Under the drought stress, the genes expression of OYDV and LYSV increased with increasing levels of drought stress compared to the control, which proved that drought stress lead to the the accumulation OYDV and LYSV and the amount increased with with the deepening of the drought.The results above indicated that the accumulation of the virus was significantly affected by the environment, and the changes of the environment further affected plant growth and development, including changes in physiology and biochemistry and cell structure. The relationship of the the amount of virus accumulation with physiological and biochemical, plasmodesmata structure need to further study and discussion.