Best time for last dose of urea application in transplanted paddy ਵੱਧ ਝਾੜ ਯੂਰਿਆ ਬੰਦ ਕਰਨ ਦਾ ਸਹੀ ਸਮਾਂ)

Prebooting Prebooting refers to the interval after the onset of internode elongation and before flag leaf formation is complete. During prebooting, the remaining leaves of the plant develop, internode elongation and stem formation continue, and panicle formation begins When cells first begin actively dividing in the growing point or apical meristem, the process is called panicle initiation (PI). This occurs during the fifth week before heading. Although it can be positively identified only by microscopic techniques, it is closely associated with certain vegetative stages of growth. The growth stages that coincide closely with PI differ depending on the maturity of a variety. In very early season varieties, PI and internode elongation (green ring) occur at about the same time. In early season varieties, PI and second internode elongation occur almost simultaneously, and in midseason varieties, PI and third internode elongation are closely concurrent. About 7 to 10 days after the beginning of active cell division at the growing point, an immature panicle about 1/8 inch long and 1/16 inch in diameter can be seen. At this point, the panicle can be seen inside the stem, resembling a small tuft of fuzz. This is referred to as panicle differentiation (PD) or panicle 2-mm The panicle, although small, already has begun to differentiate into distinct parts. Under a microscope or good hand lens, the beginnings of panicle branches and florets are recognizable. As the panicle develops, structures differentiate into a main axis and panicle branches . The growing points of these branches differentiate into florets. Florets form at the uppermost branches first and progress downward. Because there are several panicle branches, development of florets within the panicle as a whole overlaps. Florets at the tip of a lower branch might be more advanced in their development than florets near the base of an upper panicle branch. From a management stand point, panicle length defines plant development during this phase. A fungicide label, for example, might prescribe its application “from a 2- to 4-inch panicle.” By the time the panicle is about 4 inches long, individual florets can be easily recognized on the most mature panicle branches.