 In the last class we have seen the philosophy and the science of crop weather interaction that is what is crop weather interaction, types of crop weather interaction and we have given some example. In this class we like to discuss crop weather interaction directly for selected crops. These informations are mostly required to prepare our agro advisory based on the weather forecast. Past research works are available in the website as well as in many books those how to be collected and kept at the particular area where agro advisory is being prepared. For this class let us discuss the crop weather interaction for wheat crop, rice crop and maize crops. These three crops are dominant food crops of India and wheat is commonly being grown throughout the world, maize is also being grown, those crops become the staple food crops unless we understand the crop weather interaction. It is impossible to prepare agro advisory based on the weather forecast. One more thing I like to add that the whatever crop weather interaction I have given some example these are not so complete many gaps are there. Still research is required to find out the crop weather interaction for rice, wheat and maize also. With these few introduction I like to go for the rice crop. I have given only example these are not complete still we have to do some more research. If you take rice as why discussed in the cardinal temperature the rice crop tolerates up to 40 degree centigrade provided water is not a limiting factor. If water is absent suppose the rice is being raised in the dry land situation or rain front situation where moisture is not available but the temperature goes 40 degree means the rice yield has to be sacrificed. It has to lose the yield but under irrigated condition there is an adapt strategy there is a weather based decision the temperature goes beyond 40 degree centigrade means go for irrigation. Then you can ameliorate the dysfunctional aspect to be derived from your increased temperature at 40 degree centigrade. And rice also requires a mean temperature of 22 degree centigrade for the India growing period that means the mean temperature that we have discussed already the maximum temperature plus the minimum temperature divided by 2 average of these 2. So this must be around 22 centigrade this is a cardinal temperature for the growing period of the rice. If the temperature is more means if there is yield loss as we have studied in the last classes. If the night temperature is a lesser than 15 degree centigrade during the entire vegetative stage the rice yield is get affected yes the minimum temperature required for rice is 10 degree centigrade. So 15 degree itself is a dangerous limit threshold limit for losing the crop yield. So the night temperature if it is lesser than 15 degree during the entire vegetative stage the rice yield is getting affected that means that night temperature must be around 22, 23 degree centigrade. Then higher solar radiation more than 300 calories per meter square per day is required during 48 days earlier to harvest. This I was discussing in the last class when we were discussing about the radiation a cloud free environment is required from flowering to last stage other 10 days per hour to harvest or 15 days per hour so that the flowering material the pollination and seed development and milking stage everything goes on very well with the higher solar radiation of 300 calories per meter square per day. The period during which low temperature is most critical is about 10 to 14 days before getting. Heading means in the case of rice it is before flowering one stage. See if you take a rice stage as one is your nursery stage that is your developing seedling then you are transplanting seedlings in the field. So this is a seedling stage then vegetative stage this stage from transplanting to the heading flowers start coming out that is heading stage another three to four days you get flowering. So within that we have got different stages heading means three to four days earlier to flowering. See the bulge portion is coming out from the your stem portion of the rice. So in that the period during which low temperature is most critical is about 10 to 14 days before critical more critical means if the temperature is occurs this low temperature then heading may not occur that means optimum temperature is required for rice. These are all some few examples there are many examples and many gaps are there gaps must be addressed through by doing research by agro metallurgist or by agronomist. Now coming to the wheat crop it is being grown all countries of the globe world. So similar to rice I have given some example for wheat also. So withstand intense cold condition during growing season anything it is able to tolerate cold condition but does not tolerate hotness. So that is the information to be derived from this statement and during germination and growth in the temperature must be from 15 to 20 degree centigrade as we have studied the cardinial temperature when we were discussing in the last classes and high temperature during greater than 25 degree centigrade reduce the tiller numbers growth and grain yield. This is very very important especially this high temperature more than 25 degree centigrade during the vegetative stage must stop at a wheat yield and this wheat crop is sensitive to moisture stress from soothing to advancing eating stage. This is very important and there under irrigated or rainfired and at irrigated condition you must provide irrigation from soothing to advancing eating stage. In the case of the rainfired agriculture or dry land agriculture there must be rain accordingly the sowing window has to be organized otherwise we have to lose the yield then bright sometimes less harvest and colder nights during ripening period give quality grains. Quality means the protein content the carbohydrate and the self life of the grain and everything is okay. So far then bright sometimes hours with less RH that is dry atmosphere and cooler nights minimum temperature must be below 20 degree centigrade during ripening period after flowering if it occurs it gives quality grains. These are few examples for wheat crop like your rice crop. So these are all required suppose for example how to prepare agro advisory when the agro advisory says that then and the minimum temperature would be about 25 degrees centigrade and there is a cloudy environment during ripening period of your wheat then as per the Bible verse bright sunshine hours with less RH and cooler nights must be required. So cloudiness you are going to get lesser bright sunshine hours and your temperature is more than 10 minutes you will be at a hot environment. Then for that what must be done either you must go for some irrigation or some moment of strategy to make this environment that would be your agro advisory. Then coming to the maize crop another example this is very common international crop C4 crop rice is a C3 here I have given some example maize grows well in areas where the mean temperature is around 24 degree and night temperature is above 15 degree centigrade. So mean temperature as indicated for rice and other crops night maximum temperature plus minimum temperature divided by 2 when this occurs 25 degree means you will be getting higher yield from maize. Then during flowering period if the maximum temperature is around 35 degrees centigrade and more the fertilization is affected and this because what is happens the maize is a cross pollinated crop when the temperature is more than 35 degree number one the the desiccation may occur in the flowers this may lead to sterility. Another one cross pollination means either wind or insect must come above that we did in the insect do not come so your cross pollination is getting affected. So how weather plays the important role in crop protection is very very important this must be addressed before you are doing preparing the agro advisories. This maize crop requires high amount of water during flowering stage but sensitive water stagnation we need it needs water but does not require stagnation over water is not at all required the field must be brought under your either saturated conditions must be some moisture 100% moisture available soil moisture 100% must be available 80 to 100% available soil moisture but there must not be any water stagnation what will happen if water stagnation occurs in a particular crop see the maize root whatever the crops we go the root to also take needs accessence the water gets stagnated over the surface of the field means oxygen does not go into the soil profile so you root does not get oxygen and you will be getting building and the crop gets filed so that's why the crops should not be stagnated at this stage very sensitive stage flowering stage for all crops flowering stage is very very critical but this crop is something different so these are the some examples I have given and other two or three crops will be discussed by my co-faculty member professor Dr. Hor Nagarajan subsequently then I will meet you after his presentation thank you very much