A case study on the effects of irrigation and fertilization on soil water and soil nutrient status, and on growth and yield of bamboo (phyllostachys pubescens) shoots

Bamboo is one of the world's most important and versatile crops, covering extensive areas, particularly in East and Southeast Asia. There is, however, rising concern about acute scarcity of bamboo products, among which are fresh edible vegetable shoots. Appropriate agronomy and crop management may play a key role in alleviating this situation. From 1994 to 1998, we studied the effects of irrigation and compound fertilizer application on soil water and soil nutrient status, and on growth and shoot yield of Phyl!ostachys pubesce1ls established in 1990 in south-east Queensland, Australia. Water supply had a major effect on bamboo growth and shoot yield. Without irrigation and only little rainfall (80-140 mm) prior to and during the shoot season in the first 2 years of the study, shoot numbers were greater in plots closer to a supply of temporal pond water. Harvests were not made in those years. With irrigation in the following years, bamboo shoot numbers and individual shoot weights were much greater at the higher rate of irrigation. Bamboo marginally responded to increasing rates of fertilizer application; notable was the response when it was applied in the inorganic form and combined with the higher irrigation rate. Respective yields under these conditions were 8300,10 200 and 14200 kg ha-1 of shoots at 250, 375 and 500 kg Nha-1 year-I applied as compound fertilizer with N : P : K ratio of 5 : I : 2.8. Leaf nitrogen also reflected the yield response to fertilizer, but soil nitrogen did not. Response to an organic (chicken dung) form of fertilizer, albeit providing approximately one half of the rate of inorganic fertilizer, was negligible.