'Khaira' disease of rice is caused due to zinc deficiency.

In sugarcane production, seeds are not used, instead vegetative cuttings of sugarcane are used.

In this step, carbon dioxide enters and is reduced to form starch.

 The botanical name of the cotton-yielding plant is Gossypium hirsutum.

Maize is a c4 plant.

Chromosome number is fixed for a species. The lowest number is seen in Haplopapas gracilis (Asteracease), i.e. 2n = 4 and maximum in some Ophiglosum species (pteridophyte), i.e. 2n = 1656. 

 Apple scab is caused by Venturia inequalis.The disease manifests as dull black or grey-brown lesions on the surface of tree leaves, buds or fruits.

If freshly harvested grains (seeds) are stored without drying, they may get spoilt or attacked by organisms, losing their germination capacity. Hence, before storing them, grains are properly dried in the sun to reduce moisture in them. This prevents the attack by pests, bacteria and fungi.

Sprinkler system is a modern method of irrigation.