Mechanisms of Different Responses of Leaf Photosynthesis in African Rice(Oryza glaberrima Steud.) and Rice(Oryza sativa L.) to Low Leaf Water Potential.

Twenty days after rice (Oryza sativaL. ‘IR28’) emergence, water was withheld from the stress treatment for 20 days while the control was kept well-watered by furrow irrigation. In the control plots, rice leaf water potential at 0800 hours was –5.5 bars and leaf length 30 cm on the 12th day of stress. In the stress treatment, leaf water potential decreased to –8 bars and leaf length to 20 cm, when no weeds competed with rice. With maximum weed competition, rice leaf water potential decreased to –18 bars and leaf length to 15.5 cm. on the 20th day of stress, dawn (0600 h) leaf water potential of rice in the stress treatment was reduced from –8 bars when no weeds competed with rice to –19 bars when competition was maximum. The weed species had higher water potential values than the rice in both control and water-stress treatments.

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An Analysis of the Effects of Repeated Short-Term Soil Water Deficits on Stomatal Conductance to Carbon Dioxide and Leaf Photosynthesis by the Legume Macroptilium atropurpureum Cv. Siratro

Functional Plant Biology ◽

10.1071/pp9810347 ◽

1981 ◽

Vol 8 (3) ◽

pp. 347 ◽

Cited By ~ 24

Author(s):

MJ Fisher ◽

DA Charles-Edwards ◽

MM Ludlow

Keyword(s):

Stomatal Conductance ◽

Water Potential ◽

Soil Water ◽

Water Deficit ◽

Leaf Water Potential ◽

Leaf Water ◽

Mathematical Function ◽

Leaf Photosynthesis ◽

Short Term ◽

Macroptilium Atropurpureum

The response was measured of stomatal conductance and leaf photosynthesis to changing leaf water potential in the legume siratro subjected to a sequence of I-week cycles of increasing soil water deficit followed by watering. The response of stomatal conductance was described using a continuous mathematical function, which is more robust and accurate than the usual discontinuous linear function used to analyse such data. After seven successive cycles of water deficit, there was no apparent adjustment of the short-term response of leaf conductance to leaf water potential.

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KANDUNGAN AIR PADA SEGMEN DAUN TANAMAN PADI (Oryza sativa L.) LOKAL SULAWESI UTARA SAAT KEKERINGAN YANG DIINDUKSI DENGAN POLIETILEN GLIKOL 8000

JURNAL ILMIAH SAINS ◽

10.35799/jis.18.2.2018.20301 ◽

2018 ◽

Vol 18 (2) ◽

pp. 63

Author(s):

Risa Junita Mereh ◽

Nio Song Ai ◽

Parluhutan Siahaan

Keyword(s):

Oryza Sativa ◽

Water Potential ◽

Water Content ◽

Oryza Sativa L ◽

Leaf Water ◽

Leaf Segment ◽

Leaf Water Content ◽

North Sulawesi ◽

Leaf Segments ◽

Peg 8000

KANDUNGAN AIR PADA SEGMEN DAUN TANAMAN PADI (Oryza sativa L.) LOKAL SULAWESI UTARA SAAT KEKERINGAN YANG DIINDUKSI DENGAN POLIETILEN GLIKOL 8000 ABSTRAKPenelitian ini telah dilakukan untuk mengkaji kandungan air sebagai respon fisiologi pada segmen daun tanaman padi lokal Sulut (varietas Temo, Ombong, Burungan, dan Superwin) terhadap kekeringan yang diinduksi dengan PEG 8000 secara in vitro. Segmen daun padi dipotong-potong 1 cm x 1 cm dan diberi tiga macam perlakuan PEG 8000 (dengan potensial air/PA medium 0; -0,25; dan -0,5 MPa), dan empat waktu pengambilan sampel (0, 4, 8 dan 12 jam) dalam tiga kali ulangan. Hasil penelitian menunjukkan bahwa bahwa faktor varietas, faktor waktu perlakuan, faktor konsentrasi PEG 8000, dan interaksi antara ketiga faktor tersebut tidak menyebabkan perbedaan kandungan air segmen daun yang nyata.Kata kunci: Cekaman kekeringan, PEG 8000, Potensial air, Segmen daun LEAF WATER CONTENT IN LEAF SEGMENTS OF NORTH SULAWESI LOCAL RICE (Oryza sativa L.) UNDER POLYETHYLENE-GLYCOL- 8000-INDUCED DROUGHTED DROUGHTABSTRACTA study was conducted to evaluate leaf water content as one of physiological responses in leaf segments of North Sulawesi local rice (cv. Temo, Ombong, Burungan, and Superwin) under PEG 8000- induced-drought. The rice leaves were cut into 1 cm x 1 cm segments and treated withPEG 8000 solutions (medium water potential or PA of 0; -0.25; and -0.5 MPa),four sampling times (0, 4, 8 and 12 hours) and 3 replicates. The results indicated that factors of varieties, treatment period, concentration of PEG 8000, and interaction among these factors did not result in any differences in water content of rice leaf segments.Keywords: Drought stress, PEG 8000, Water potential, Leaf segment

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Distribution and accumulation of mercury in pot-grown African rice cultivars (Oryza glaberrima Steud. and Oryza sativa L.) determined via LA-ICP-MS

Environmental Geochemistry and Health ◽

10.1007/s10653-021-01169-6 ◽

2022 ◽

Author(s):

Tracy Punshon ◽

Brian P. Jackson ◽

Alexis Donohue ◽

Chuan Hong ◽

Sarah E. Rothenberg

Keyword(s):

Oryza Sativa ◽

Oryza Sativa L ◽

Oryza Glaberrima ◽

Rice Cultivars ◽

African Rice ◽

Icp Ms

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Endophytes from African Rice (Oryza glaberrima L.) Efficiently Colonize Asian Rice (Oryza sativa L.) Stimulating the Activity of Its Antioxidant Enzymes and Increasing the Content of Nitrogen, Carbon, and Chlorophyll

Microorganisms ◽

10.3390/microorganisms9081714 ◽

2021 ◽

Vol 9 (8) ◽

pp. 1714

Author(s):

Carmen Bianco ◽

Anna Andreozzi ◽

Silvia Romano ◽

Camilla Fagorzi ◽

Lisa Cangioli ◽

...

Keyword(s):

Oryza Sativa ◽

Antioxidant Enzymes ◽

Nitrogenase Activity ◽

Oryza Sativa L ◽

Tropical Region ◽

Oryza Glaberrima ◽

Bacterial Endophytes ◽

African Rice ◽

Asian Rice ◽

Temperate Climates

Bacterial endophytes support the adaptation of host plants to harsh environments. In this study, culturable bacterial endophytes were isolated from the African rice Oryza glaberrima L., which is well-adapted to grow with poor external inputs in the tropical region of Mali. Among these, six N-fixer strains were used to inoculate O. glaberrima RAM133 and the Asian rice O. sativa L. cv. Baldo, selected for growth in temperate climates. The colonization efficiency and the N-fixing activity were evaluated and compared for the two rice varieties. Oryza sativa-inoculated plants showed a fairly good colonization efficiency and nitrogenase activity. The inoculation of Oryza sativa with the strains Klebsiella pasteurii BDA134-6 and Phytobacter diazotrophicus BDA59-3 led to the highest nitrogenase activity. In addition, the inoculation of ‘Baldo’ plants with the strain P. diazotrophicus BDA59-3 led to a significant increase in nitrogen, carbon and chlorophyll content. Finally, ‘Baldo’ plants inoculated with Kl. pasteurii BDA134-6 showed the induction of antioxidant enzymes activity and the maintenance of nitrogen-fixation under salt stress as compared to the unstressed controls. As these endophytes efficiently colonize high-yielding crop varieties grown in cold temperate climates, they become good candidates to promote their growth under unfavorable conditions.

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