Methods and compositions for the inhibition of meristematic growth on cucurbit rootstock

Abstract

The invention provides methods of inhibiting the growth of a shoot apical meristem of a cucurbit rootstock plant, comprising contacting a shoot apical meristem of the cucurbit rootstock plant with an effective amount of a composition comprising one or more fatty alcohols, thereby inhibiting the growth of the shoot apical meristem of the cucurbit rootstock plant. The present invention further provides methods for preparing and producing cucurbit rootstock plants for grafting and methods for grafting. Additionally provided are cucurbit rootstock plants and plant parts and grafted cucurbit plants produced by the methods of the invention.

1 - 31 . (canceled) 
     
     
         32 . A grafted cucurbit plant comprising:
 (a) a cucurbit rootstock plant comprising:
 (i) a shoot apical meristem chemically killed by contacting the shoot apical meristem of the rootstock plant with an effective amount of a composition comprising one or more fatty alcohols, 
 (ii) a hypocotyl having increased fresh weight, increased dry weight, increased width and an increased level of at least one nonstructural carbohydrate as compared to a hypocotyl of a cucurbit rootstock plant that has not had its shoot apical meristem contacted with the composition but is otherwise grown under the same conditions, wherein the nonstructural carbohydrate is glucose, sucrose, fructose and/or starch, and the level of the nonstructural carbohydrate is increased by about 0.2 μg/g to about 8 μg/g by about day 14 to about day 21 post treatment with the composition, and 
 (iii) no cotyledons; and 
   (b) a cucurbit scion grafted to the cucurbit rootstock plant.   
     
     
         33 . The grafted cucurbit plant of  claim 32 , wherein the composition comprises N-hexanol fatty alcohol (C 6 ), N-octanol (C 8 ) fatty alcohol, N-decanol (C 10 ) fatty alcohol, N-dodecanol (C 12 ), N-tetradecanol, or any combination thereof. 
     
     
         34 . The grafted cucurbit plant of  claim 32 , wherein the composition comprises N-octanol (C 8 ) fatty alcohol and/or N-decanol (C 10 ) fatty alcohol. 
     
     
         35 . The grafted cucurbit plant of  claim 33 , wherein the composition comprising one or more fatty alcohols comprises 0.5% C6 fatty alcohol, 42% C8 fatty alcohol, 56% C10 fatty alcohol, 1.5% C12 fatty alcohol and 15% inert ingredients (FAIR 85®); 36.2% C8 fatty alcohol, 48.2% C10 fatty alcohol, 0.3% C12 fatty alcohol and 15.3% other ingredients (Offshoot-T®); 0.5% C6 fatty alcohol, 42% C8 fatty alcohol, 56% C10 fatty alcohol, 1.5% C12 fatty alcohol and 15% other ingredients (Sucker Plucker®); or any combination thereof. 
     
     
         36 . The grafted cucurbit plant of  claim 32 , wherein the composition comprises a concentration of 2% (volume/volume) to about 40% (volume/volume) of fatty alcohols or about 2% (volume/volume) to about 20% (volume/volume) of fatty alcohols. 
     
     
         37 . The grafted cucurbit plant of claim  31 , wherein the cucurbit rootstock plant is a wild watermelon rootstock plant, a bottle gourd rootstock plant, an interspecific squash rootstock plant, figleaf gourd, wax gourd,  C. moschata, Cucumis hystrix  Chakrav.  Cucumis hytivus  J. F. Chen & J. H. Kirkbr.,  Cucumis metuliferus  E. Mey ex Naud,  Cucumis melo , and/or other wild-type cucurbit. 
     
     
         38 . The grafted cucurbit plant of  claim 37 , wherein the bottle gourd rootstock plant is  Lagenaria  spp. or  Lagenaria siceraria , the interspecific squash rootstock plant is  Cucurbita maxima×Cucurbila moschata , the figleaf gourd is  Cucurbita ficifolia , the wax gourd is  Benincasa hispida  and the wild-type cucurbit is  C. lanatus, Citrulus lanatus  subsp.  lanatus  ‘Ojakkyo’,  Citrullus lanatus  subsp.  mucosospermus, Cucumis africanus , or  Cucumis myriocarpus.    
     
     
         39 . The grafted cucurbit plant of  claim 32 , wherein the cucurbit rootstock is a bottle gourd plant and the scion is a watermelon plant ( Citrullus lanatus  subsp.  lanatus ). 
     
     
         40 . The grafted cucurbit plant of  claim 32 , wherein the cucurbit rootstock plant is an interspecific squash rootstock plant and the scion is a watermelon plant ( Citrullus lanatus  subsp.  lanatus  or  Citrullus lanatus  subsp.  mucosospermus )), a melon plant ( Cucumis melo ), an oriental melon plant ( Cucumis melo  var.  makuwa ) or a cucumber plant ( Cucumis sativus ). 
     
     
         41 . The grafted cucurbit plant of  claim 32 , wherein the cucurbit rootstock plant is a figleaf gourd plant and the scion is a cucumber plant. 
     
     
         42 . The grafted cucurbit plant of  claim 32 , wherein the cucurbit rootstock plant is  Cucurbita moschata  and the scion is a cucumber plant or a watermelon plant. 
     
     
         43 . The grafted cucurbit plant of  claim 32 , wherein the cucurbit rootstock plant is wild watermelon ( Citrullus lanatus  subsp.  lanatus  or  Citrullus lanatus  subsp.  mucosospermus ) and the scion is a watermelon plant. 
     
     
         44 . The grafted cucurbit plant of  claim 32  wherein the cucurbit rootstock plant is  Cucumis melo  var.  makuwa  and the scion is a melon plant. 
     
     
         45 . The grafted cucurbit plant of  claim 32 , wherein the cucurbit rootstock plant is wax gourd and the scion is a watermelon plant. 
     
     
         46 . The grafted cucurbit rootstock plant of  claim 32 , wherein the cucurbit rootstock plant grafted to the cucurbit scion is characterized by a grafting success rate that is increased by at least about 25% as compared to a control cucurbit rootstock plant grafted to a cucurbit scion in which the shoot apical meristem of the control cucurbit rootstock plant was not chemically killed by contact with an effective amount of a composition comprising one or more fatty alcohols.