Application of 1% ethyl ester of napthaleneacetic acid (NAA) in an aqueous or latex formulation to trunk and scaffold branches of pruned lemon trees [C. limon (L.) Burm.] did not affect yield during the season of application or during the year following application. Regrowth of trunk and limb sprouts was controlled for approximately 1 year.
Response surface methodology was utilized in statistical optimization of three quality factors (the number of multiple shoots, shoot length, and number of leaves) pertaining to regeneration of plantlets from leaf calli of Decalepis hamiltonii Wight. & Arn. (swallow root). The variables evaluated were the levels of sucrose, BA, and NAA each at two different concentrations. Response surfaces for shoot length and multiple shoot number were useful in achieving optimal levels of media constituents and in understanding their interactions, but response surfaces for number of leaves were not. The data indicate that sucrose, BA, and NAA levels may be manipulated to increase or decrease quality factors chosen. This approach may be useful in developing a micropropagation protocol for D. hamiltonii. Chemical names used: benzyladenine (BA); napthaleneacetic acid (NAA).
Naphthaleneacetic acid (NAA) and 1-naphthyl N-methyl carbamate (carbaryl) applied separately in both dilute and concentrated sprays significantly increased fruit size; however, when butanedioic mono-2,2-dimethylhydrazide (daminozide) was added, fruit size remained about the same as on unsprayed check trees. Crop load was not significantly affected by any of these treatments. Dilute and concentrated sprays of carbaryl produced more return bloom than did NAA. The most effective treatments were combinations of NAA and carbaryl, either dilute or concentrated. Combining first-cover pesticides [azinphosmethyl (guthion) and cis-N-(trichloromethyl)thio)-4-cy-clonexane-l,2-dicarboximide (captan)] with NAA, and captan with carbaryl, produced satisfactory thinning.
Naphthaleneacetic acid (NAA) sprayed as a 1% ethyl ester or sodium salt formulation below the grafts effectively controlled trunk and limb sprouts on topworked fig trees (Ficus carica L.). Reduction of scion growth and numbers of sprouts on unsprayed portions of grafted limbs indicated translocation of NAA for a distance of at least 10 cm.
To compare the effects of growth regulators on preharvest fruit drop and fruit maturity, aminoethoxyvinylglycine (AVG) was applied to `McIntosh' apple trees at 75, 150, or 225 mg·L-1, at 8, 4, or 2 weeks before harvest (WBH). These treatments were compared to NAA, daminozide, and to an untreated control. All AVG treatments and timings except 75 mg·L-1 applied 8 WBH delayed preharvest drop and fruit maturity. AVG applied at 225 mg·L-1was more effective in delaying drop and development of maturity than other rates when applied 8 or 2 WBH, but at 4 WBH, 150 mg·L-1 gave equivalent results to 225 mg·L-1. AVG at 150 mg·L-1 was superior to NAA or daminozide as a stop-drop agent. No concentration, or time of application of AVG influenced fruit size at harvest. AVG reduced internal ethylene concentration (IEC) in `McIntosh' apples linearly with increasing AVG concentration. There was a linear relationship between time of AVG application (8, 4, or 2 WBH) and IEC in the fruit after harvest, and the time required for harvested fruit to enter the ethylene climacteric. Development of red color was delayed by AVG. This was attributed to a delay in ripening as determined by a slower increase in IEC and starch hydrolysis. In general, earlier application of AVG resulted in reduced effectiveness of lowering IEC following harvest. Chemical names used: aminoethoxyvinylglycine (AVG), naphthaleneacetic acid (NAA), succinic acid-2,2-dimethylhydrazide (daminozide).
Translocation of l4C-sucrose from leaf to fruit was measured in ‘Golden Delicious’ and ‘Staymared’ apple (Malus domestica Borkh.) and ‘Redhaven’ peach (Prunus persica (L.) Batsch) following the application of compounds reported to influence fruitlet abscission. Succinic acid-2,2-dimethylhydrazide (daminozide) reduced 14C translocation in both apple cultivars but reduced fruit set only in ‘Golden Delicious’. Ethephon reduced 14C translocation and fruit set of peach. Abscisic acid (ABA) and 2,4-dinitrophenol (DNP) reduced 14C-sucrose translocation in apple. Enclosing apple limbs in black cloth bags reduced fruit set and naphthaleneacetic acid (NAA) increased leaf water potential. One method of preliminary screening of compounds for apple fruit thinning may be based on their effect on 14C-sucrose translocation from foliage to fruit.
Specific auxin-containing formulations which contained primarily indolebutyric acid (IBA), and/or napthaleneacetic acid (NAA) were most effective in promoting rooting of terminal stem cuttings of poinsettia (Euphorbia pulcherrima Willd.).
aminoethoxyvinylglycine [AVG ( Layne et al., 2002 )] and affecting abscission physiology via a synthetic auxin, 1-napthaleneacetic acid [1-NAA ( Nartvaranant, 2018 )]. The objectives of our 2020 haskap field trials were to record PHFD rates among haskap cultivars
Inflorescence slices of tall bearded iris (Iris sp.) regenerated callus in vitro on a modified Murashige-Skoog high salt medium supplemented with 2.5 mg/liter napthaleneacetic acid (NAA) and 0.5 mg/liter kinetin. Callus pieces transferred to light initiated plantlets at their periphery and produced fuU-sized, true-to-type flowering plants when transplanted to soil.
Shoot segments of Grevillea rosmarinifolia A. Cunn. placed on solid half-strength Murashige and Skoog (MS) medium containing 0.5 mg/liter 6-benzyiamino purine (BA) proliferated and formed shoots which were subcultured and rooted on paper bridges in Murashige and Skoog medium containing 0.1 mg/liter α-napthaleneacetic acid (NAA).
