 In the last class, we had a discussion on the crop production risk and weather sensitiveness. These are all output from what. So for deriving those information, we must understand the crop weather interaction. In a family of wife and husband, there must be an interaction between these two. Then only the family would be sustainable, must be positive interaction, like that. The crop is a biological component. The weather is a physical component, both are different. In the case of a family life, both are biological. Here physical interacts with bio-organisms. So interaction is something different. Those must be known earlier so that crop sensitiveness and production risk would be addressed very correctly for developing a better advisory. And those things we will be discussing in this class. So crop weather interaction, what is that? I have raised a question. Climate influenced the distribution of crops over different regions of the world while weather influenced the crop production and productivity. This we had discussed earlier very well. Then the crop yields are the integrated result of environmental and physiological process that occur during crop moving period. Here I say is the physiological process of the crop land, physiological means your food production that is photosynthesis, flowering, everything is controlled by your environmental factors. Environmental is nothing but climate or weather. Plus soil also, somebody says that if you talk about environmental it also must address your soil or regional component also. But here I am taking only environmental means, the weather and climate. And it has got good impact or better impact on the physiological process that happen in a planned system or crop system. The environment is the climate which regulates and determines the growth and development and final output of the crops. Very very important. The weather induced variability in crop yield is high as 50% WMO, World Meteorological Organization. These we have discussed already in the crop production risk. What I want to say is there is positive interaction, there is negative interaction between these two fellows I give life to your climate or weather. And also another life to the plant system also. Now see crop other interaction what is that? Crop other interaction can be called in the other way as bio physical interaction as I indicated earlier. Bio means plant, physical means river climate. The action is given by physical matter like weather and the plant as a bio organism respond to the action in a positive way. If the action is favorable or on the other way, negative way if the action is unfavorable. When the action is favorable, positive interaction. When the action is not favorable, it is a negative interaction and those things we could see in the next slide. So I have given four interaction, fermentation combination of direct, indirect, positive and negative. So positive direct action of climate or weather on crops. Positive and indirect impact on plant by the climate. Negative direct on the plant by the climate or weather. Negative indirect impact on the crop from the weather or climate. Let us see what are those? Now examples I have given. Positive direct plant growth, I can say crop yield increase. When the weather is favorable, yield is more against 20% more, 30% more. You can say that the weather is good, weather was good during the season, good rainfall, good temperature. So it is a direct impact on the crop production. Positive indirect NCM action less pest and disease. NCM action within the plant it happens, we do not know what is going inside the plant system. This is indirect effect and less pest and disease. These are also examples. And overall negative direct effect crop yield decline opposite to positive direct. Crop yield is lost, drought crop is lost, flood drought is lost, crop yield is lost. Normal code, it is a positive interact. So if you take three weather codes, your normal weather code is giving positive direct. Your flood situation and the drought is always giving negative direct effect. For example, this we had discussed earlier in our lessons. Negative indirect pest and disease is epidemic, epidemic means suddenly there is incidence of pest or disease. This happens always in some part of all countries at different seasons. Now response of crops to weather elements, that must be understood. This also we had discussed in the first week when we were discussing about the weather elements. Radiation, radiation comes from sun directly that we call it as radiation. That is shortwave radiation directly comes from the sun. It is, if you want to define this shortwave radiation in terms of micron, 0.4 micron, 2.7 micron. So with the receipt of this visible light, we can say also a visible light. The drain water protection is increased through net higher photosynthesis by the plant. Light, short day plant, long day plant, day neutrals, photoperiatism. So there are short day plants, there are long day plant, there are day neutrals and photoperiatism. So it is an adaptation capacity based on the light and the plant has a different capacity. This is a good interaction. The rainfall soil moisture and transport of nutrients and plant tragedy. See in 80% of human body contains moisture, in 80% of the plant voids contains moisture. Otherwise tragedy, no tragedy. So rainfall is very, very important whether it is from groundwater or through rainfall. Rainfall is a direct groundwater is indirect from rainfall. Temperature, enzyme and hormone activity in plants. Cell division, multiplication and all biochemical relations. Respiration, translocation of synthetics. Here respiration is very, very important. I can relate a temperature. If the night temperature is more than the optimum, then there is production loss. Normally in a particular area the night temperature would be around 24 to 25 degree temperature. That is minimum temperature. The temperature is 30 degree centigrade. The synthetics that was stored in the morning or in the before the stages. Will be used to make respiration. So it is a loss. So temperature has got both the direct and indirect effect. Relative humidity already we have discussed. Outbreak of disease. Pestimidivis. And again of soil moisture, high orchids, triggers higher growth and more flowering. Especially for C4 plants as we discussed earlier. Dew. Recovery loss of torque of leaves reduced the transpiration with the soil moisture saving. Dew is very, very important for your residue crop management. That is the trap crop or something else. So north India, Bengal gram and other crops are being grown as your residue crop. So for that dew is very, very important to meet their moisture requirement. Wind as we discussed earlier, preventing frost CO2 by horizontal movement of photosynthetics. What I like to say is each weather element has important role on your crops. Suppose radiation. See it helps for dry matter protection through photosynthesis. See I was telling about rice crop interaction. When the cloud environment exists at the time of flowering of rice to harvest. Then your dry matter protection, your rice grain maturity will be reduced. Its development will be reduced and you are going to get reduced yield. So for example we take radiation, positive impact is dry matter protection through higher photosynthesis. If the higher radiation does not occur, what will happen? The product will be lost. That for example I can take it from rice. The radiation is not available from flowering to our maturity milking stage. And before 10 days, before harvest, physiological maturity, radiation does not occur. Then there will be yield loss. When the radiation does not occur because of the cloudiness, clouds may block your radiation being received from sun to your crops. So this is a good example. Like that for all weather elements, I have given the response of the crops. If these are blocked, I think the yield is going to be affected. That is a message to be obtained from this class. Thank you very much.