Low night temperatures during the early growth phase enhance flowering in primocane shoots of red raspberries (Rubus idaeus L.)

Cassava (Manihot esculenta Crantz) experiences intermittent water deficit and suffers from potassium (K) deficiency that seriously constrains its yield in the tropics. Currently, the interaction effect between deficit irrigation and K fertigation on growth and yield of cassava is unknown, especially during the early growth phase. Therefore, pot experiments were conducted under controlled greenhouse conditions using cassava cuttings. Treatments initiated at 30 days after planting included three irrigation doses (30%, 60%, 100% pot capacity) and five K (0.01, 1, 4, 16, and 32 mM) concentrations. The plants were harvested 90 days after planting. Decreasing irrigation dose to 30% together with 16 mM K lowered the leaf water potential by 69%, leaf osmotic potential by 41%, photosynthesis by 35%, stomatal conductance by 41%, water usage by 50%, leaf area by 17%, and whole-plant dry mass by 41%, compared with full-irrigated plants. Lowering the K concentration below 16 mM reduced the values further. Notably, growth and yield were decreased the least compared with optimal, when irrigation dose was decreased to 60% together with 16 mM K. The results demonstrate that deficit irrigation strategies could be utilized to develop management practices to improve cassava productivity by means of K fertigation under low moisture conditions.

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BIOSYNTHESIS OF NICOTINIC ACID BY FUSARIUM OXYSPORUM SCHLECHT

Canadian Journal of Biochemistry ◽

10.1139/o67-228 ◽

1967 ◽

Vol 45 (12) ◽

pp. 1953-1959 ◽

Cited By ~ 7

Author(s):

D. Desaty ◽

L. C. Vining

Keyword(s):

Nicotinic Acid ◽

Fusarium Oxysporum ◽

Acid Hydrolysis ◽

Growth Phase ◽

Sodium Acetate ◽

Fusaric Acid ◽

Early Growth ◽

Pyridine Derivatives ◽

Early Growth Phase ◽

Hydrolysis Of

When the fungus Fusarium oxysporum was cultured on a glucose–nitrate–salts medium, synthesis of nicotinic acid occurred only during the early growth phase and preceded the accumulation of fusaric acid. Radioactivity from DL-tryptophan-benzene ring-14C was efficiently incorporated into nicotinic acid obtained by acid hydrolysis of the mycelium, whereas DL-tryptophan-β-14C, L-aspartate-U-14C, and sodium acetate-2-14C were poor precursors. Under the conditions of these experiments, all four substrates were poor precursors of fusaric acid. It is concluded that different pathways are used in the biosynthesis of these two pyridine derivatives, the route to nicotinic acid probably involving metabolism of tryptophan via the reactions known to occur in Neurospora crassa.

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Effects of benzyladenine and α-naphthaleneacetic acid on the early growth phase of Ananas comosus (L.) Merr.

Science and Technology Development Journal - Natural Sciences ◽

10.32508/stdjns.v1it4.482 ◽

2017 ◽

Vol 1 (T4) ◽

pp. 5-13

Author(s):

Ut Van Le ◽

Mai Thi Bach Vo

Keyword(s):

Cell Size ◽

Growth Phase ◽

Early Growth ◽

Ananas Comosus ◽

Naphthaleneacetic Acid ◽

Negative Effects ◽

Pineapple Fruit ◽

Early Growth Phase

In this study, benzyladenine (BA) and α- naphthaleneacetic acid (NAA) are used to study the growth of pineapple fruit (Ananas comosus (L.) Merr.) in the early growth phase. Pineapple fruits are sprayed with BA or NAA at different concentrations (1, 5, 10, 20, 40 and 60 mg.L-1) at both 0 and 3 days after flowering (DAF, 50 % dried flowers). Fruits are sampled every 15 days from 0 to 75 days to survey to weight, size and qualities of pineaple fruit. Besides, fruits (which are sprayed with BA or NAA at concentration 20 mg.L-1) are sampled at 15 days for the cell size observation. The results showed that the treatments with three highest concentration of BA or NAA (20, 40 và 60 mg.L-1) significantly increased fruit weights and fruit sizes. Exogenous BA or NAA at the concentration 20 mg.L-1 increased the fruit weights by increasing the number of flesh cells without negative effects on fruit qualities.

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