Short communication: Physiological response to drought in North Sulawesi (Indonesia) local rice (Oryza sativa) cultivars at the tissue level in hydroponic culture

Abstract

Abstract. Nio SA, Mereh RJ, Ludong DPM. 2021. Short communication: Physiological response to drought in North Sulawesi (Indonesia) local rice (Oryza sativa) cultivars at the tissue level in hydroponic culture. Biodiversitas 22: 58-64. Water availability influenced the metabolism processes in the plants and this condition could change water balance in the cells as well as restricting the growth and production of crops. This study aimed to evaluate the effect of in vitro polyethylene glycol (PEG) 8000-induced water deficit on the relative water content and chlorophylls (total, a, and b) concentration as physiological response in leaf segments of North Sulawesi (Indonesia) local rice cultivars (cvs. Superwin, Ombong, Burungan, and Temo). The rice leaves were cut into 1 cm x 1 cm segments and were treated under both control (0 MPa) and water deficit (-0.25 and -0.5 MPa) using PEG 8000 as osmoticum. The experiment was factorial completely randomized block design with 4 sampling times (0, 4, 8, and 12 hours) and three replicates. Interaction of water deficit duration and PEG 8000 treatment resulted in a significant difference in leaf relative water content. The leaf relative water content at PEG -0.5 MPa after 8 and 12 hours of treatments was lower than at control (PEG 0 MPa) when the treatment commenced (0 hour). The concentration of chlorophylls (total, a, and b) were significant differences among cultivars and water deficit durations. This study showed that leaf relative water content was a potential physiological indicator of PEG 8000-induced water deficit in North Sulawesi local rice at the tissue level in hydroponic culture.

Short Communication: Morphophysiological Response to Partial Submergence and Water Deficit in North Sulawesi Local Rice

“…The qualified seeds were collected and sterilized using a 2% commercial bleach solution to rinse the seeds three times for 2-3 minutes for each rinse, washed with boiled water three times and then the seeds were soaked for overnight. Before planting, each pot that already contained soil was watered until field capacity (Nio & Ludong, 2014). The seeds were planted on the planting medium in the pots (volume 1,500 mL).…”

“…After the plants were 12 days old, one plant was selected to be used in each pot. Watering the plants to field capacity was continued until the plants reached the four-fully-expanded-leaf stage (Nio & Ludong, 2014). Well-watered (control), partial submerged, and water deficit treatments were then commenced and lasted for 14 days.…”

“…The level of losses in plants due to drought depended on several factors, including the time drought commenced, the intensity and the duration of water deficit (Nio, 2010). Water deficit induced by polyethylene glycol 8000 in local rice from North Sulawesi decreased the content of chlorophyll a and total (Nio et al, 2019) and the relative water content of the leaves (Nio et al, 2021).…”

Respon Morfofisiologi Padi Varietas Sulutan Dan Rindang 1 Pada Fase Vegetatif Di Bawah Naungan Pohon Kelapa

“…Hasil penelitian ini diharapkan dapat memberikan informasi mengenai respons morfofisiologi padi Sulutan dan Rindang 1 yang ditanam di bawah naungan pohon kelapa dan sekaligus mengkaji potensi padi Sulutan sebagai varietas padi lokal yang tahan naungan. Nio et al, 2021).…”

“…Selanjutnya, benih padi yang telah disterilisasi ditanam langsung di wadah dengan 10 lubang tanam dan 3 benih padi ditanam pada tiap lubang dengan kedalaman 1 cm. Terakhir, wadah yang sudah ditanami ditutup dengan kertas koran yang basah sampai tanaman berkecambah (modifikasi Nio et al, 2021).…”