Sugarcane is one of the most important crops in the tropics, and it is also becoming an important crop in the subtropics, meaning that it is cultivated between the latitudes of 35°N and 35°S. It covers a total acreage of 20.1 million ha, yielding a global production of 1,317.9 million metric tons of cane with an average cane productivity of 65.6 t ha −1 (FAO 2004). On the other hand, sugarcane has the theoretical potential to yield 470 t ha −1 dry matter, 805 t ha −1 wet cane, 50-78 t ha −1 sucrose, and has a total solar energy harvesting efficiency of 8.5%. The highest harvestable sugarcane yield achieved so far is close to 58% of its theoretical potential. In other words, there is a 42% gap between the theoretical yield of sugarcane and the highest harvestable sugarcane yield obtained so far. Efforts are now underway to bridge this gap and thus increase the productivity of sugarcane. Such efforts include the use of high-yielding varieties, fertilizers, irrigation, different types of effluents, sewage sludge, industrial residues/by-products, spent wash, pesticides, herbicides, etc. Except for the use of high-yielding cane varieties, these methods of increasing cane productivity add heavy metals to the soils for growing sugarcane.

Staling impacts bud-sett moisture and nutrients like sucrose and reducing sugar contents of seed cane/setts. With increase in staling time bud and sett moisture, sucrose % juice decreased whereas total soluble solids and reducing sugars increased. Germination % ( at 45 DAP) and fresh weight of settlings (at 55 DAP) decreased with increasing staling time. Bud moisture affected germination and fresh weight of settlings more than the sett moisture. These growth parameters were positively influenced by sucrose content and negatively by reducing sugars and total soluble solids ( o Brix).The negative influence of the total solids could be due to non-sugars like phenolics, etc.

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Poor sugarcane ratoon yields in the subtropics are responsible for decrease in overall productivity and poor sugar recovery. The present work is an attempt to assess reasons for decline in crop productivity despite providing adequate inputs. The simultaneously initiated plant and ratoon crops were compared for dry-matter accumulation and its distribution pattern in relation to changes in soil-root interface environment. In spite of well-established root system and advanced sprouting and tillering during the formative phase, dry-matter accumulation and nutrient uptake were low in a ratoon crop and were more apparent 120-210 days after planting. This decrease in nutrient uptake was due to declines in soil cation-exchange capacity, nitrate reductase (NR) activity in vivo by 19.4 and 25.9 percent, and increase in percentage leakage by 11.26 percent. These alterations at the soil-root interface in ratoons functioned as barriers for nutrient uptake and affected overall physiological growth and dry-matter accumulation adversely.