Performance of durum wheat cultivars and advanced lines to black point under natural conditions in two crop seasons

Twenty seven advanced durum wheat lines and cultivars CIRNO C2008, Baroyeca Oro C2013, and Quetchehueca Oro C2013 were evaluated for their reaction to black point, under natural conditions at the Norman E. Borlaug Experimental Station, in the Yaqui Valley, Sonora, Mexico, during crop seasons 2015-2016 and 2016-2017. Sowing dates were November 12 and 19, 2015, for the first season, and November 17 and 24, 2016 for the second one, using 8 g of seed for a 0.7 m bed with two rows without replications. Harvest was done manually and the evaluation by visual inspection counting the number of healthy and infected grains in ten spikes per line/cultivar, in order to determine the percentage of infection. Based on the average of the two dates, in the first season one line did not show any infected grain, ten fell within the 0.1-2.5 % infection category, six within 2.6-5.0 %, three within 5.1-10.0 %, and seven within 10.1-30 %. Quetchehueca Oro C2013 did not show any infected grain, while CIRNO C2008 and Baroyeca Oro C2013 showed 1.7 and 12.3 % infection, respectively. In the second season, two lines did not show infected grains, seventeen lines and the three cultivars with 2.4, 1.5, and 1.0 %, respectively, fell within the 0.1-2.5 % infection category, six within 2.6-5.0 %, and two within 5.1-10.0 %. Lines with the highest percentage of infection were: 1A.1D5+1-06/3*MOJO//RCOL/4/ ARMENT//SRN_3/NIGRIS_4/3/CANELO_9.1/5/CF4-JS40//SOOTY_9/RASCON_37/4/CNDO/PRIMADUR//HAI-OU_17 /3/SNITAN/9/CBC509CHILE/6/ECO/CMH76A.722//BIT/3/ALTAR84/4/AJAIA_2/5/KJOVE_1/7/AJAIA_12/ F3LOCAL(SEL.ETHIO.135.85)//PLATA_13/8/S with 50.4 % in the first date of the first season, and WBDTBO/10/ PLATA_10/6/MQUE/4/USDA573//QFN/AA_7/3/ALBA-D/5/AVO/HUI/7/PLATA_13/8/THKNEE_11/9/CHEN/ ALTAR84/3/HUI/POC//BUB/RUFO/4/FNFOOT/11/MÂALI/10/ALTAR84/CMH82A.1062//ALTAR 84/3/YAZI_10/4/ SNITAN/9/USDA595/3/D67.3/RABI//CRA/4/ ALO/5/HUI/YAV_1/6/ARDENTE with 16.3 % in the second date of the second season. Higher infection was detected in crop season 2015-2016 possibly to the occurrence of higher relative humidity during grain expansion.