Intercropping Tuber Crops with Teak in Gunungkidul Regency, Yogyakarta, Indonesia

Abstract

The adoption of agroforestry system aims to combine food production enhancement to compensate population growth with the improvement of agricultural marketable products to increase household income. The diversification of food crop products requires more effective land use. In Gunungkidul, high-density teak (Tectona grandis) plantation has dominated many private forests. The area under the tree crown has received low light intensity, where only shade-resistant plants can survive. Tuber crops, i.e., arrowroot (Maranta arundinacea), canna (Canna edulis) and yam (Dioscorea esculenta) are shade-tolerant crops, which were planted in tree understory for supplementary food production and income generation. The cultivation under teak stand has been overlooked due to uncertainty in tuber productivity. To address this knowledge gap, the effect of teak shade (5- and 7-year teak) on the growth and yield of the three tuber crops was examined. The results indicated that both teak trial areas (with RLI 45.13% and 38.76%) were suitable for canna production (LER > 1), while management options were recommended for enhancing arrowroot and yam production. The LER of intercropped three-tuber crops under 5 years’ teak were >1, while of those under 7 years’ teak, only canna reached >1. Canna is the preferred option to be mixed in teak agroforestry systems with low light intensity due to its consistent yields, whether planted in open area or under teak shade. Silvicultural management, pruning and thinning are recommended to increase the growing space and resource sharing for intercropped plants. Land optimization in private forest understory using shade-resistant tubers will offer medium-term benefits, provided that proper silvicultural procedures are applied.

The effects of teak shades at different ages on early growth of 3 tuber species in Semin Village, Gunung Kidul

“…The level of shade was measured using relative light intensity (RLI). The RLI of the research area under five years teak was 45.13%, while under seven years teak was 38.76% and 100% on open area (8). The difference in the morphological adaptation of the three types of tuber plants can be seen in Figures 1 and Figure 2.…”

Agricultural Land Dryness Distribution Using the Normalized Difference Drought Index (NDDI) Algorithm on Landsat 8 Imagery in Eromoko, Indonesia

“…The plantation has the highest percentage area in a moist category based on the condition of the planted land having dense canopy, which causes little sunlight to reach the soil resulting in low evaporation (Shahidan et al, 2007). The existence of teak gives lower light intensity, as much as 45.13% (5 years teak) and 38.76% (7 years teak), which will reduce evaporation and micro temperature so the soil moisture will be maintained (Maharani et al, 2022). A cover crop of the plantation is often found to cause a decrease in solar radiation received by the soil and maintain soil moisture by evaporation (Kaye and Quemada, 2017;O'Connell and Snyder, 1999).…”

Productivity of Clonal Teak Plantation Under Different Spacing and Thinning Intensity in Java Monsoon Forest

“…Initially, most community teak forests were established with a spacing of 3m x 3m, following the planting pattern of Perum Perhutani, without thinning (Wahyudi et al, 2014). With the development of science, teak plantations began to be designed with larger spacing and thinning to increase productivity, one of which was the initial spacing of 6 m x 2 m. This spacing has also been successful in increasing teak productivity and accommodating agroforestry systems (Prehaten et al, 2021;Rahmawati et al, 2021;Maharani et al, 2022). In addition, the combination of plant genetic quality and initial spacing is a silvicultural consideration to increase forest productivity (Isaac-Renton et al, 2020).…”