Response of some upland rice varieties to drought stress

Abstract

Abstract. Purwanto E, Samanhudi, Yoniar Effendi Y. 2017. Response of some upland rice varieties to drought stress. Trop Drylands 1: [69][70][71][72][73][74][75][76][77]. The study aimed to examine the response of upland rice varieties at germination stage on several PEG (Polyethylene Glycol) 6000 concentration levels and to determine growth characteristics, physiological changes and yield of upland rice varieties under drought stress condition in a pot experiment. The study consisted of two experiments; the first was to study germination and early growth, and the second was to study the vegetative and generative growth of upland rice under drought stress condition. Experiments I and II were conducted in a completely randomized factorial design consisted of two factors and three replications. In experiments I, the first factor was upland rice variety comprised of 10 varieties and the second factor was PEG concentration consisted of four levels. In experiment II, the first factor was upland rice varieties that responded the best to drought stress in experiment I, and the second factor was the drought stress treatment consisted of moisture content at 100, 75, 50 and 25% field capacity. The research was conducted at the Laboratory of Plant Physiology and Biotechnology and the greenhouse of Faculty of Agriculture, Sebelas Maret University (UNS) Surakarta. The results showed that the germination and vigor index decreased with increasing levels of PEG concentration. PEG concentration of 25 g L -1 of water was the most optimum for screening drought resistant upland rice. In experiment I, Towuti, Situ Patengang, Kalimutu and Gajah Mungkur varieties showed the best response to drought stress. Increased intensity of drought stress resulted in a reduction of plant height, number of tillers, dry weight, relative growth rate, leaf area, number of grains hill -1 , 1000 grain weight, dry grain weight hill -1 and root dry weight. The drought stress also caused an earlier flowering date and increased percentage of empty grain. Based on the dry grain weight hill -1 , Towuti exhibited a higher drought resistance level than Gajah Mungkur, Situ Patenggang and Kalimutu.

Selection of upland rice lines in advanced yield trials and response to abiotic stress

“…Plants will adjust photosynthates partitioning among the organs under drought conditions. Drought stress increases the root-shoot ratio, indicating that photosynthates are partitioned more toward root formation and reduces canopy growth (Purwanto et al 2017).…”

“…Drought recovery refers to the plants' capability to resume growth after experiencing the adverse effects of drought stress (Purwanto et al 2017). The plant recovery ability evaluation showed that lines E33-CK1-BP, E38-CK1-BP, CG9-53-1-3, and Salumpikit as a drought-tolerant check variety were categorized as tolerant (Table 10).…”

Respon pertumbuhan sorgum manis (Sorghum bicolor L.) terhadap pemberian air yang berbeda

“…Dalam kondisi tercekam kekeringan, tinggi tanaman beberapa aksesi sorgum biasanya mengalami penurunan (Widiyono et al, 2020). Hal ini juga sesuai dengan pendapat (Purwanto, Samanhudi, & Effendi, 2017), bahwa peningkatan intensitas cekaman kekeringan mengakibatkan penurunan tinggi tanaman. Penurunan tinggi tanaman yang signifikan mulai terjadi pada kadar air tanah sebesar 50% kapasitas lapang.…”

Respons Tanaman Kentang terhadap Jenis Zat Pengatur Tumbuh pada Berbagai Kondisi Cekaman Kekeringan di Dataran Medium

“…Semakin lama interval waktu penyiraman tampak semakin menurunkan nilai ILD. Hal ini diduga karena respons tanaman terhadap cekaman kekeringan dilakukan dengan menurunkan luas daun untuk mengurangi kehilangan air dari transpirasi (Tourneux et al, 2003 (Purwanto et al, 2017).…”