Search Results

You are looking at 1 - 10 of 27 items for

  • Author or Editor: S. B. Boswell x
  • Refine by Access: All x
Clear All Modify Search
Open access

S. B. Boswell and W. B. Storey

Abstract

Sprays of a synthetic cytokinin, 6-(benzylamino)-9-(2-tetrahydropyranyl)-9H-purine (PBA), applied to seedlings of Macadamia tetraphylla L. in the greenhouse resulted in sprouting of axillary buds, and reduced growth of the terminal shoot. Terminal removal caused lateral shoot development in more seedlings than PBA.

Open access

H. Hield, S. B. Boswell, and Stuart Hemstreet

Abstract

Painting of inhibitors on pruning cuts reduced growth only in the area proximal to treatment in Eucalyptus globulus Labill. Sprays of 0.2 to 0.3% 1-propylphosphonic acid (NIA 10656) or injection of 8 ml of 10% tech grade NIA 10656 gave shoot growth reduction for 1 year. Ethyl hydrogen 1-propylphosphonic acid (EHPP, NIA 10637) showed responses similar to NIA 10656. Naphthaleneacetic acid (NAA), EHPP, NIA 10656 and amonium ethyl carbamoylphosphonate (Krenite) all showed certain growth regulator responses when painted on pruning cuts. Inhibitors applied in an asphalt carrier to cuts were more effective than similar applications in a water carrier. Application of 6, hydroxy-3-(2H) pyridacinone (MH), trifluromethyl sulfonamido-p-acetotoluidide (Sustar), NAA and EHPP combination, or methyl 2-chloro-9-hydroxyfluorene-9-carboxylate (chlorfluernol methyl ester, principal active ingredient in Maintain CF 125) were tested as trunk bark bands for reduction in terminal shoot growth. The Maintain CF 125 product diluted with an equal amount of diesel oil and applied in a band equal to the trunk diameter of E. camaldulensis Denhardt effected a reduction in terminal growth 11 months after banding. Maintain CF 125 applied at full product strength (12.5%) or diluted equally with water and the other inhibitors tested did not cause growth reduction.

Open access

E. M. Nauer and S. B. Boswell

Abstract

Newly budded trees of ‘Valencia’ orange [Citrus sinensis (L.) Osbeck] on rough lemon (C. jambhiri Lush.), alemow (C. macrophylla Wester), Troyer citrange (Poncirus trifoliata Raf. ⨯ C. sinensis), and P. trifoliata were sprayed with 2 concentrations of naphthaleneacetic acid (NAA) to inhibit rootstock sprouting, buds being protected with budding tape. Good control of rootstock sprouts was obtained on rough lemon and P. trifoliata but translocated NAA inhibited scion bud initiation. There was partial suppression of rootstock sprouts on Troyer citrange but no scion bud inhibition. NAA did not control rootstock sprouts on alemow.

Open access

E. M. Nauer and S. B. Boswell

Abstract

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.

Open access

E. M. Nauer and S. B. Boswell

Abstract

Application of 6-benzylamino purine (BA) to quiescent citrus buds generally increased the percentage of buds to initiate active growth. Results of 2 years’ experimentation were highly variable and revealed several factors, such as season and cultivar, which influence the efficacy of BA for stimulating citrus buds into growth. BA was more effective outdoors and in a screenhouse than in a greenhouse. There was appreciable variation among several citrus cultivars. Early spring applications in a commercial citrus nursery were more effective than late spring or summer applications with ‘Owari’ satsuma (Citrus reticulata Blanco) budded on Troyer citrange (Ponci-rus trifoliata [L.] Raf. × C. sinensis [L.] Osbeck) rootstock.

Open access

S. B. Boswell, B. O. Bergh, and R. H. Whitsell

Abstract

A 1% ethyl ester or sodium salt formulation of naphthaleneacetic acid (NAA) in 30% aqueous solution of white latex paint sprayed below the grafts effectively controlled trunk sprouts in topworked avocados (Persea americana Mill). Regrowth was suppressed over a 7-month growing period with no adverse effects on the grafts.

Open access

S. B. Boswell, E. M. Nauer, and W. B. Storey

Abstract

Application of 6-(benzylamino)-9-(2-tetrahydropyranyl-9H-purine (PBA); 6-benzylamino purine (BA); and ethyl 5-(4-chlorophenyl)-2H-tetrazole-2-acetate (PP528) to seedlings of Macadamia tetraphylla L. in the greenhouse resulted in sprouting of axillary buds. PBA and BA were more effective than PP528. No axillary buds sprouted on untreated seedlings.

Open access

M. R. Kaufmann, S. B. Boswell, and L. N. Lewis

Abstract

The effect of tree spacing on the root distribution of 9-year old ‘Washington’ navel orange trees on ‘Troyer’ citrange rootstock was studied. Spacings ranged from 9 ft x 15 ft to 22 ft x 22 ft. Roots were washed from soil cores (3-ft deep, 4-inch diam) taken at 2-ft intervals along 2 transects, 1 across the row and 1 along the row and beneath an irrigation furrow. The distribution of both small roots (1.5 mm in diam or smaller) and large roots was affected by tree spacing and by location of the irrigation furrow. At close springs, many soil cores contained about 4 g dry wt of small roots, suggesting that the soil contained as many feeder roots as possible under those conditions. Wider spacings had fewer roots per core. Evidence suggests that considerable overlapping of root systems occurred at close spacings but not at the wider spacings. It is likely that root competition will limit yield during the next decade at the closer spacings, whereas considerable room for root growth exists at wide spacings.

Open access

S. B. Boswell, R. M. Burns, and H. Z. Hield

Abstract

Sprays of a plant growth regulator ammonium ethyl carbamoylphosphonoate (Krenite), applied to top regrowth of mature Lisbon lemon trees [Citrus limon (L.) Burmann] resulted in significant inhibition of growth for over 1 year. At concentrations above 0.2% there was excessive foliar and small branch damage.

Open access

S. B. Boswell, E. M. Nauer, and D. R. Atkin

Abstract

Trees of old-line ‘Atwood’ navel orange [Citrus sinensis (L.) Osbeck] on Rubidoux trifoliate orange [Poncirus trifoliata (L.) Raf.] rootstock were planted in 1970 at 6 different spacings in 5 replications to determine effects of tree spacing on fruit quality, tree growth, yield, air temperature, light penetration, and production costs. Growth rate was measured by trunk circumference and tree height. Trunk circumference increased as spacing increased. Closely spaced trees were 0.7 m higher than widely spaced trees after 9 years. Fruit quality analyses showed no differences until the trees began to crowd. Fruit colored faster in 1980 on the widely spaced trees than on closely spaced trees. Fruit from trees spaced 5.5 × 5.5 m reached legal maturity (8:1, solids:acid ratio) 12 days ahead of fruit from trees spaced 2.7 × 4.6 m.