RESPONSE OF YIELD AND QUALITY OF SWEET POTATO PLANTS TO IRRIGATION INTERVALS AND SOME SOIL AND FOLIAR APPLICATION TREATMENTS

Document Type : Original Article

Author

Potato and Vegetatively Propagated Vegetables Dept. Hort. Res. Inst., Agric. Res. Center, Giza, Egypt.

Abstract

A field experiment was carried out during the two successive  summer  seasons of 2019 and 2020 in a Private Farm at Meet Faris Village, Dekarns, District  Dakhlia  Governorate, Egypt to study the effect of irrigation intervals  (15 and 30 days) and  some  soil application treatments  (humic acid at 20 kg /fad. and fulvic acid at 10 kg/fad.) and foliar  application treatments (without,  trehalose at 1 g/l,  potassium silicate at 1ml/l and algae extract at 1g/l)  on growth, plant water relationships,  yield and its components as well as  tuber roots quality of sweet potato plants cv. Beauregard grown  under clay soil conditions  using  follow  irrigation system .
The obtained results showed that,  the interaction  treatment between irrigation sweet potato plants cv Beauregard grown in clay soil during summer seasons conditions every 15 or 30 days and treated plants with fulvic acid  at 10 kg /fad. as soil application  + spraying  with  potassium silicate  at 1 ml/l  increased main vine  length , both fresh and dry weight of shoots/ plant, average tuber root weight , total yield/fad.  and K contents  in tuber roots.  In addition, the interaction between   irrigation every 15 and treating with fulvic acid at 10 kg /fad. as soil application+ foliar spray with potassium silicate at 1 ml/l increased number of branches/plant, marketable yield  and total carbohydrates  in tuber roots. Also  the  plants  grown under the same irrigation intervals (every 15 days)  and treating with fulvic acid  at 10 kg /fad.+  spraying with trehalose at 1 g/l  significantly increased total , free water  in leaf  tissues  , however  , the interaction between  irrigation  every 15 days intervals  and treating with  fulvic acid  at  10 kg /fad. as soil application+  spraying with  algae extract  at 1 g/l increased N and P in shoots and tuber roots as well as  tuber root diameter.  On the other hand,  the interaction between irrigation every 30 days  and treated plants  with FA at 10 kg /fad.+ spraying  with potassium silicate  at 1 ml/l  increased  K contents in shoots , tuber root length and dry matter contents in tuber roots. The interaction between irrigation every 30 days  and treating with  humic acid only at 20 kg /fad increased  bound water (%) , osmotic pressure  and proline amino acid  in leaves  of sweet potato in both growing seasons
Conclusively, it could be concluded that, irrigation sweet potato plants grown in clay soil during summer seasons every 15 or 30 days  and treated plants with  fulvic acid  at 10 kg /fad. soil application + spraying with  potassium silicate  at 1 ml/l or  with algae extract  or  trehalose at 1 g/l of each to obtain high  productivity  and  best  tuber root quality.
 

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