EFFECT OF NOZZLE TYPES , SPRAY VOLUMES AND RATE OF GLYPHOSATE ON DROPLET NUMBERS, DROPLET SIZES AND ITS EFFICIENCY ON WEED CONTROL IN CITRUS ORCHARDS | ||||
| Journal of Plant Protection and Pathology | ||||
| Article 1, Volume 32, Issue 7, July 2007, Page 5623-5634 PDF (551.95 K) | ||||
| Document Type: Original Article | ||||
| DOI: 10.21608/jppp.2007.219695 | ||||
 View on SCiNiTO | ||||
| Authors | ||||
| M. R. Moshtohry,1; A. E. Ammar2 | ||||
| 1Weed Res. Central laboratory | ||||
| 2Plant Protection Res. Institute, Spray technology dep. Agriculture Research Center , Giza, Egypt | ||||
| Abstract | ||||
| Two field experiments were carried out in Horticulture Research Station at El-Kanater , Kalubia Governorate during 2003 and 2004 summer seasons at Navel orange trees 15 years old orchard naturally heavily infested with annual and perennial weeds. Each experiment included eleven treatments in a complete randomized block design with four replicates . Four nozzles were applied in these treatments i.e. hollow cone ( conventional method ) at rates of glyphosate ( Round up 48 %WSC) 4.0 , 2.5 L/fed. and 1.25 L/fed., withTK1 nozzle at 2.5 and 1.25 L/fed, flat and fan E 04 – 80 nozzle at 2.5 and 1.25 L/fed . and deflector yellow nozzle at 2.5 and 1.25 L/fed. as compared with hand hoeing and unweeded check. Water volumes were 200, 125, 102 and 50 L/fed. with the previous nozzles in the same respective . The aim of this study is to compare various nozzles types , spray volumes and glyphosate rates on number of droplets / cm², droplet size μm and weed control efficiency . Results of study indicate that using TK1 , flat fan E 04 – 80 and deflector yellow nozzles can reduced glyphosate rate to 2.5 L/fed. by 37.5% compared with conventional method with hollow cone at 4.0 L/fed. without effect on weed control efficacy .These nozzles improved spray spectrum by increasing number of droplets to 35 – 57/ cm2 in the first season and 39 – 55/ cm2 in the second season and decreasing droplet size to 367 – 200 and 360 – 205 μm in the first and second seasons , respectively as compared to hollow cone nozzle which gave 17 and 20 droplet/ cm² with 679 and 669 μm for both seasons , respectively at the same rate of 2.5 L/fed. Control percentage which obtained by these nozzles were 93.2, 92.2 and 90.1 % in the first season and 95.7, 94.5 and 93.5% in the second season , respectively, as compared with hollow cone which gave 94.3 and 97.2 % for the first and second seasons at 4.0 L/fed., respectively. On the other hand the low rate of glyphosate at 1.25 L/fed. gave good efficacy in controlling annual weeds which reached 89% control percentage for these weeds and exceeded hand hoeing . Thus it could be concluded that these nozzles can reduce spray volume and glyphosate rate without any significant reduction in the control efficacy of total weeds accompanied with homogeneous distribution and decreasing the amount of herbicide drift which fallen in non targets crops during the application and consequently decrease the pollution and other possible risks on the environment . | ||||
|
Statistics Article View: 56 PDF Download: 179 |
||||
