CHANGE OF PHOTOSYNTHETIC ACTIVITY AND PRODUCTIVITY EARLY-MATURING HYBRID OF CORN THE CASCADE DEPENDING ON DENSITY OF STANDING AND BACKGROUND A MINERAL FOOD IN UPPER VOLGA
Influence of various density of standing (60, 70, 80, 100 thousand / hectare) and backgrounds a mineral food (without application of fertilizers, with application of fertilizers on an increase 100, 200, 300, 400 ts/hectares and productivity of 400 ts/hectares) on photosynthetic activity and efficiency of corn is studied. It is established that increase of density of standing to 100 thousand / hectare background a mineral food increases the average area of leaves by all on 58 - 72 %, the maximum area of leaves on 52 - 94 % and photosynthetic potential in 1,7 - 2 times. The increase in the average area of leaves from background a mineral food, in comparison with not fertilized background, has made 35 - 61 %, the maximum area of leaves 45 - 86 %. The maximum photosynthetic potential of crops has been generated on 4 and 5 backgrounds it has made 2,03 and 1,90 million м2 х days/hectares. Net productivity of photosynthesis increased from increase of density of standing, than from strengthening of a background of a mineral food so from 1 to 5 background it increased consistently (g/m2 х days) on 0,23 more; 2,13; 1,23; 2,1 and 0,82, and from increase in density of standing with 60 to 100 thousand / hectare in 1,3 - 2,1 times. On all backgrounds fertilizers the greatest crop of crude and dry phytoweight provides crops of corn with density of 100 thousand / hectare. The maximum size they have reached on backgrounds NPK on an increase of 400 ts/ hectares and NPK on productivity of 400 ts/hectares of 368 and 352 ts/hectares crude and 53,1 and 64,3 ts/hectares of dry phytoweight. In the conditions of 2009 and 2010, at density of standing of 100 thousand / the hectare has been received the programmed increase of a crop of green weight in 200 ts/hectares and close to planned a crop in 400 ts/hectares, the shortage has made 12 %