Effect of harvesting with a trunk shaker and an abscission chemical on fruit detachment and defoliation of citrus grown under Mediterranean conditions
Abstract
Spain ranks as the world’s leading exporter of citrus for fresh consumption. Manual harvest accounts for 50% of the total production costs. Mechanical harvest would increase labor productivity and benefits of growers. Efficiency of these machines depends on the varieties and operating conditions. Use of abscission chemicals has been promoted to increase the detachment rate of fruit without affecting its quality. This work is aimed at studying whether the mechanical harvest and/or the application of an abscission agent affect the quality and quantity of harvested fruit and tree defoliation under the conditions of citrus cultivation in Spain. Trials were made in a completely randomized experimental design. From 2008 to 2011, different orchards of mandarin and orange trees were sprayed with different doses of ethephon as abscission agent and harvested with a trunk shaker. Harvest related variables (detachment percentage, defoliation and fruit without calyx) were measured. The percentage of fruit detached by the trunk shaker ranged between 70 and 85% and it did not depend on the orchard. The shaker produced minimal damage to the bark when gripped incorrectly. Increased doses of ethephon increased fruit detachment except in ‘Clemenules’ orchard, but also increased the fruit without calyx in 1-9%. Moreover, ethephon promoted significant defoliation. Neither gummosis nor death of branches was observed. This work demonstrates that mechanical harvesting with trunk shakers may be a feasible solution for citrus cultivated in Spain for fresh market. Use of ethephon could only be recommended for citrus destined to industry and only for certain varieties.
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References
Alférez F, Pozo L, Burns JK, 2006. Physiological changes associated with senescence and abscission in mature citrus fruits induced by 5-chloro-3-methyl-4-nitro-1H-pyrazole and ethephon application. Physiol Plant 127: 66-73. http://dx.doi.org/10.1111/j.1399-3054.2006.00642.x
BenSalem E, Salyani M, Whitney JD, 2001. Spray variable effects on deposition and harvesting efficacy of CMN-Pyrazole. Proc Fla State Hort Soc 114: 111-118.
Bukovac MJ, 1979. Machine-harvest of sweet cherries: effect of ethephon on fruit removal and quality of the processed fruit. J Am Soc Hortic Sci 104(3): 289-294.
Burns JK, 2002. Using molecular tools to identify abscission materials for citrus. HortScience 37: 459-464.
Burns JK, 2008. 1-Methylciclopropene applications in preharvest systems: focus on citrus. HortScience 43: 112-114.
Burns JK, Hartmond U, Kender WJ, 1999. Acetolactate synthase inhibitors increase ethylene production and cause fruit drop in citrus. HortScience 34(5): 908-910.
Burns JK, Pozo L, Yuan R, Hocknema B, 2003a. Guanfacine and clonidine reduce defoliation and phytotoxicity associated with abscission agents. J Am Soc Hortic Sci 128 (1): 42-47.
Burns JK, Alférez F, Pozo L, Arias C., Hocknema B, Rangaswamy V, Bender C, 2003b. Coronatine and abscission in citrus. J Am Soc Hortic Sci 128 (3): 309-315.
Burns JK, Pozo L, Morgan K, Roka F, 2006a. Better spray coverage can improve efficacy of abscission sprays for mechanically harvested oranges. Proc Fla State Hort Soc 119: 190-194.
Burns JK, Roka, F, Li K-T, Pozo L, Buker R, 2006b. Late-season 'Valencia' Orange mechanical harvesting with an abscission agent and low-frequency harvesting. HortScience 41(3): 660-663.
CLAM, 2010. Les exportation d'agrumes du bassin méditerranéen. Statistiques, evaluations, repartitions. Situation 2009-2010. Secretariat General de C.L.A.M., Madrid, Comité de Gestión de Cítricos.
Ebel RC, Burns JK, Morgan KT, Roka F, 2010. Abscission agent application and canopy shaker frequency effects on mechanical harvest efficiency of sweet oranges. HortScience 45(7): 1079-1083.
Farooq M, Salyani M, Whitney JD, 2002. Improving efficacy of abscission sprays for mechanical harvesting of oranges. Proc Fla State Hort Soc 115: 247-252.
González-Sicilia E, 1968. El cultivo de los agrios. Ed. Bello. Valencia, Spain.
Hartmond U, Whitney JD, Burns JK, Kender WJ, 2000a. Seasonal variation in the response of ´Valencia´ orange to two abscission compounds. HortScience 35: 226-229.
Hartmond U, Yuan R, Burns JK, Grant A, Kender WJ, 2000b. Citrus fruit abscission induced by methyl-jasmonate. J Am Soc Hortic Sci 125(5): 547-552.
Jiménez-Cuesta M, Cuquerella J, Martínez-Jávega JM, 1981. Determination of color index for citrus fruit degreening. Proc Int Soc Citriculture 2: 750-753.
Junta de Andalucía, 2014a. Costes medios de producción. Campaña 2011-2012. Mandarina. Available in www.juntadeandalucia.es/agriculturaypesca/servlet/frontController?action=Costes&ec=subsector&subsector=21&table=3945.
Junta de Andalucía, 2014b. Costes medios de producción. Campaña 2011-2012. Naranja. Available in www.juntadeandalucia.es/agriculturaypesca/servlet/frontController?action=Costes&ec=subsector&subsector=21&table=3945.
Juste F, Martín B, Fabado F, Moltó E, 2000. Estudio sobre la reducción de los costes de producción de cítricos mediante la mecanización de las prácticas de cultivo. Todo Citrus 8: 29-36.
Kender WJ, Hartmond U, Yuan R, Pozo L, Grant A, 2000. Factors influencing the effectiveness of ethephon as a citrus fruit abscission agent. Proc Fla State Hort Soc 113: 88-92.
Klein I, Epstein E, Lavee S, Ben-Tal Y, 1978. Environmental factors affecting ethephon in olive. Scientia Hort 9: 21-30. http://dx.doi.org/10.1016/0304-4238(78)90105-X
Koo YM, Salyani M, Whitney JD, 1999. Effects of abscission chemical spray deposition on mechanical harvest efficacy of 'Hamlin' orange. Proc Fla State Hort Soc 112: 28-33.
Levene H, 1960. Robust tests for equality of variances, in contributions to probability and statistics: essays in honor of Harold Hotelling, (Olkin I, Ghurye SG, Hoeffding W, Madow WG & Mann HB, eds). Stanford Univ. Press, Palo Alto, CA, USA, pp: 278-292.
Li KT, Syversten JP, 2004. Does mechanical harvesting hurt your trees? Citrus Industry 85: 30-33.
Li KT, Syversten JP, 2005. Mechanical harvesting has little effect on water status and leaf gas exchange in citrus trees. J Am Soc Hortic Sci 130: 661-666.
Li KT, Syversten JP, Burns JK, 2005. Mechanical harvesting of Florida citrus trees has little effect on leaf water relations or return bloom. Proc Fla State Hort Soc 118: 22-24.
Li KT, Syversten JP, Dunlop J, 2006. Defoliation after harvest with a trunk shaker does not affect canopy light interception in orange trees. Proc Fla State Hort Soc 119: 187-189.
Li KT, Burns JK, Syversten JP, 2008. Recovery from phytotoxicity after foliar application of fruit-loosening abscission compounds to citrus. J Am Soc Hortic Sci 133(4): 535–541.
MARM, 2010. Anuario de Estadística, 2010. Ministerio de Medio Ambiente y Medio Rural y Marino, Madrid. Available in http://www.marm.es/estadistica/pags/anuario/2010/AE_2010_Avance.pdf.
Martin GC, Lavee S, Sibbett GS, 1981. Chemical loosening agents to assist mechanical harvest of olive. J Am Soc Hortic Sci 106: 325-330.
Ortiz C, Torregrosa A, 2013. Determining the adequate vibration frequency, amplitude and time for the mechanical harvesting of fresh mandarins. T ASABE 56(1): 15-22. http://dx.doi.org/10.13031/2013.42581
Peterson DL, 1998. Mechanical harvester for process oranges. Appl Eng Agr 14(5): 455-458. http://dx.doi.org/10.13031/2013.19409
Pozo L, Burns JK, 2000. Ethylene action inhibitors reduced Ethrel-induced leaf drop and gummosis in citrus. Proc Intl Soc Citricult IX Congr 1: 578-579.
Pozo L, Burns JK, 2006. 1-Methylcyclopropene reduces fruitlet loss caused by ethephon foliar sprays. Proc Fla State Hort Soc 119: 183-186.
Pozo L, Burns JK, 2009. Organ loss and yield impacts of 'Valencia' sweet orange in response to fruit abscission agents. HortScience 44(1): 83-88.
Pozo L, Redondo A, Hartmond U, Kender WJ, Burns JK, 2004. Dikegulac promotes abscission in citrus. HortScience 39(7): 1655-1658.
Ramos DE, 1997. Walnut production manual. Univ Calif Agric Nat Resour Publ Nº 3373.
Rasmussen GK, 1977. Loosening of oranges with pik-off, release, acti-aid and sweep combinations. J Am Soc Hortic Sci 90: 4-6.
Suits DB, 1957. Use of dummy variables in regression Equations. J Am Statist Assoc 52: 548-551. http://dx.doi.org/10.1080/01621459.1957.10501412
Sumner HR, 1973. Selective harvesting of Valencia oranges with a vertical canopy shaker. T ASAE 16(6): 1024-1026. http://dx.doi.org/10.13031/2013.37686
Syversten JP, 1994. Partial shoot removal increases net CO2 assimilation and alters water relations of citrus seedlings. Tree Physiol 14: 497-508. http://dx.doi.org/10.1093/treephys/14.5.497
Torregrosa A, Porras I, Martín B, 2010. Mechanical harvesting of lemons (cv. Fino) in Spain using abscission agents. T ASABE 53(3): 703-708. http://dx.doi.org/10.13031/2013.30062
Torregrosa A, Ortí E, Martín B, Gil J, Ortiz C, 2009. Mechanical harvesting of oranges and mandarins in Spain. Biosyst Eng 104: 18-24. http://dx.doi.org/10.1016/j.biosystemseng.2009.06.005
Warner HL, Leolpold AC, 1969. Ethylene evolution from 2-chloroethylphosphonic acid. Plant Physiol 44: 156-158. http://dx.doi.org/10.1104/pp.44.1.156
Wheaton TA, Wilson WC, Holm RE, 1977. Abscission response and color changes of ˈValenciaˈoranges. J Am Soc Hortic Sci 102(5): 580-583.
Whitney JD, 1995. A review of citrus harvesting in Florida. Trans Citrus Eng Conf 41: 33-60.
Whitney JD, 1997. Field test results with mechanical citrus fruit removal devices. Proc Fla State Fort Soc 110: 89-92.
Whitney JD, 2003. Trunk shaker and abscission chemical effects on yields, fruit removal, and growth of orange trees. HortTechnology 13(2): 344-351.
Whitney JD, Wheaton TA, 1987. Shakers affect Florida orange fruit yields and harvesting efficiency. Appl Eng Agr 3(1): 20-24. http://dx.doi.org/10.13031/2013.26637
Whitney JD, Churchill DB, Hedden SL, 1986. A five-years study of orange removal with trunk shakers. Proc Fla State Hort Soc 99: 40-44.
Whitney JD, Hartmond U, Kender WJ, Burns JK, Salyani M, 2000a. Orange removal with trunk shakers and abscission chemicals. Appl Eng Agr 16(4): 367-371. http://dx.doi.org/10.13031/2013.5217
Whitney JD, Hartmond U, Kender WJ, Salyani M, Burns JK, 2000b. Abscission chemicals affect trunk shaker. Proc Fla State Hort Soc 113: 93-96.
Wilson WC, Holm RE, Clark, RK, 1977. Abscission chemicals-Aid to citrus fruit removal. Proc Int Soc Citric 2: 404-406.
Wilson WC, Coppock GE, Clark JA, 1981. Growth regulators facilitate harvesting of oranges. Proc Int Soc Citric 1: 278-281.
Yang SF, 1969. Ethylene evolution from 2-chloroethylphosphonic acid. Plant Physiol 44: 1203-1204. http://dx.doi.org/10.1104/pp.44.8.1203
Yuan R, Burns, JK, 2004. Temperature factor affecting the abscission response of mature fruit and leaves to CMN-Pyrazole and ethephon in ´Hamlin´ oranges. J Am Soc Hortic Sci 129(3): 287-293.
Yuan R, Hartmond U, Grant A, Kender WJ, 2001a. Physiological factors affecting response of mature ´Valencia´ orange fruit to CMN-Pyrazole. I. Effects of young fruit, shoot, and root growth. J Am Soc Hortic Sci 126: 414-419.
Yuan R, Hartmond U, Kender WJ, 2001b. Physiological factors affecting response of mature ´Valencia´ orange fruit to CMN-Pyrazole. II. Endogenous concentrations of indole.3-acetic acid, abscisic acid, and ethylene. J Am Soc Hortic Sci 126: 420-442.
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