Nader Assad*(1)
Safaa Kumari(2) Amin Haj-Kassem(3) Salah Al-Chaabi(4)
and Attia Arab(4)
(1).
AlGhab Research Center, General Commission for Scientific Agricultural Research
(GCSAR), Damascus, Syria.
(2).
Torbol Station, International Center for Agriculture Research in Dry Area
(ICARDA), Albekaa, Lebanon.
(3).
Department of Plant Protection, Faculty of Agriculture, Aleppo University,
Aleppo, Syria.
(4).
General Commission for Scientific Agricultural Research (GCSAR), Damascuse,
Syria.
(*Corresponding
author: Nader Assad. E-Mail: asaad_nader@yahoo.com).
Received: 21/03/2020 Accepted: 12/05/2020
Abstract
Field experiments were carried out during 2017/2018 cropping season
to study the effect of three planting dates (5 December, 25 December and 15
January) and five seed rates (80, 100, 120, 140 and 160 kg/ha) in two different
sites/locations (Al Ghab Research Center and Jeb Ramleh Research Station/
Syria) on the chickpea infection with luteoviruses (aphid-born persistently
transmitted viruses), which causing yellowing and stunting symptoms under
natural infections. Tissue blot-immunoassay (TBIA) results showed that
luteoviruses (family Luteoviridae) were the main causal of stunting and
yellowing symptoms on randomly selected chickpea plants. High level of
significant differences (P < 0.001) were recorded within the two
experimental sites/locations. The early sowing date (5 December) reduced the
percence of virus incidence by 75 and 85%, and grain yield were increased by
3.5 and 30.9% compared to other sowing dates (25 December and 15 January,
respectively). Also, incidence of luteoviruses was reduced by 41% and
remarkable enhancement of grain yield up to 28% was recorded on the second
sowing date (25 December) compared to 3rd planting date (15
January). Disease incidence differed significantly (P< 0.001) at all levels
of seeding rates, and it decreased gradually (2.7> 1.9> 1.5> 0.97>
0.63 %) in contrary to increased seeding rates (80< 100< 120< 140<
160 kg/ha, respectively). In addition, significant interactions were recorded
between planting date and seed rate treatments, whereas the best treatment
which was recorded when planting at the rates of 100 and 120 kg/h in early date
(5 September), and the highest grain yield were 2,495 and 2,487 kg/ha,
respectively, with low luteovirus incidence (0.5 and 0.45%, respectively). On
the other hand, increasing of seed rates up to 140 and160 kg/ha played a
positive role by decreasing the rate of virus infections by 64.3 and 76.7%,
respectively, and enhancing the grain yield up to 25.7 and 30%, respectively
when planting date was late on (15th January), to the contrary of
early planting date where high seed rates resulted into negative effects on the
grain yield. The highest parameters (except the disease severity levels) were
significantly recorded (P<0.001) in Al Ghab Research Center in comparison to
that of Jeb Ramleh Research Station with rates of 12, 40 and 39.5% for grain
yield, infected plants per plot and disease incidence %, respectively; and in
general, the performance of parameters were somehow similar in both locations
with some differences.
Keywords: TBIA, chickpea, seed rate, planting dates, Syria, Luteoviruses.
Full paper in English: PDF