** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** PULSE CROPS ARE AN IMPORTANT PART OF FARMING SYSTEMS AND PROVIDE SEVERAL BENEFITS INCLUDING A REDUCTION IN DISEASES, WEEDS, PEST OUTBREAKS, AND COMMERCIAL NITROGEN APPLICATIONS FOR THE NEXT ROTATION CROPS WHILE IMPROVING SOIL HEALTH AND FERTILITY. CHICKPEA IS AN IMPORTANT PULSE CROP IN THE US, GROWN ON ABOUT HALF A MILLION ACRES IN 2019 MAINLY IN FOUR STATES (MONTANA 35%, WASHINGTON 32%, IDAHO 19%, AND NORTH DAKOTA 9%). THE US PRODUCTION IS IMPORTANT FOR THE INTERNATIONAL MARKET AS ~70% OF THE COOL SEASON PULSES INCLUDING CHICKPEA ARE EXPORTED. DESPITE A SIGNIFICANT INCREASE IN THE AREA UNDER CHICKPEA PRODUCTION, THE PRODUCTIVITY IS QUITE LOW WITH A YIELD GAP OF ABOUT 84% BETWEEN THE GENETIC POTENTIAL (5.3T/HA) AND ACTUAL YIELD (780KG/HA). AMONG VARIOUS FACTORS, BIOTIC AND ABIOTIC STRESSES ARE MAINLY RESPONSIBLE FOR THE YIELD GAP. A MAJOR BIOTIC FACTOR LIMITING CHICKPEA PRODUCTION GLOBALLY IS ASCOCHYTA BLIGHT (AB) CAUSED BYASCOCHYTA RABIEI. UNDER IDEAL ENVIRONMENTAL CONDITIONS, THIS DEVASTATING DISEASE CAN CAUSE 100% YIELD LOSS.CURRENTLY, THE DISEASE MANAGEMENT IS DONE VIA INTEGRATED PEST MANAGEMENT STRATEGIES INCLUDING DELAYED SOWING, PROLONGED ROTATION, AND FUNGICIDE APPLICATION. RECENT REPORTS OF FUNGICIDE-RESISTANT AB ISOLATES HAVE RENDERED THE USE OF A POPULAR FUNGICIDE (QOI) INEFFECTIVE.GENETIC RESISTANCE ALONG WITH GOOD MANAGEMENT STRATEGIES IS THE MOST ECONOMICAL, EFFECTIVE, AND ENVIRONMENTALLY FRIENDLY APPROACH FOR MANAGING THE DISEASE.MOST OF THE CURRENTLY AVAILABLE HIGH-YIELDING CHICKPEA VARIETIES ARE HOWEVER EITHER SUSCEPTIBLE OR CARRY ONLY PARTIAL RESISTANCE. SYSTEMATIC EVALUATION OF THE CULTIVATED CHICKPEA GERMPLASM HAS IDENTIFIED FEW SOURCES OF RESISTANCE PROVIDING ONLY PARTIAL RESISTANCE, MOST OF WHICH HAVE ALREADY BEEN EXPLOITED.WILD RELATIVES OFCHICKPEAREPRESENT A SOURCE OF UNTAPPED VARIATION FOR MANY VALUE-ADDED TRAITS INCLUDING BIOTIC AND ABIOTIC STRESS TOLERANCE. A VERY HIGH LEVEL OF RESISTANCE TO AB HAS BEEN REPORTED IN WILD SPECIES INCLUDINGCICER PINNATIFIDUM,C. JUDAICUM,C. BIJUGUM, ANDC. ECHINOSPERMUM.NO PRACTICAL METHOD IS CURRENTLY AVAILABLE TO TRANSFER THIS HIGH LEVEL OF RESISTANCE IN A PRECISE AND TARGETED MANNER. CURRENTLY AVAILABLE METHODS TO TRANSFER VALUE-ADDED GENES FROM WILD UN-ADAPTED GERMPLASM TO CULTIVATED CHICKPEA ARE CUMBERSOME AND GENERALLY RESULT IN THE TRANSFER OF A WHOLE CHROMOSOME, ARM OR LARGE CHROMOSOMAL SEGMENTS THAT CARRY THOUSANDS OF UNDESIRABLE GENES. THIS IS DUE TO THE PRESENCE OF STRICT CHROMOSOME PAIRING AND RECOMBINATION CONTROL. BECAUSE OF THE STRINGENT HOMOEOLOGOUS CHROMOSOME PAIRING CONTROL, CHROMOSOMES OF WILD RELATIVES DO NOT PAIR OR RECOMBINE WITH THE CHICKPEA CHROMOSOMES DURING ALIEN INTROGRESSIONS RESULTING IN THE TRANSFER OF WHOLE CHROMOSOMES/ARMS OR LARGE SEGMENTS THAT ALMOST ALWAYS CARRY UNWANTED TRAITS (LINKAGE DRAG). THUS, A TARGETED ALIEN GENE TRANSFER METHOD IS REQUIRED TO TRANSFER VALUE-ADDED GENES SUCH AS THAT FOR AB RESISTANCE, IN A TARGETED MANNER. ONCE OPTIMIZED, THE APPROACH CAN THEN BE USED FOR THE TRANSFER OF OTHER VALUE-ADDED GENES FROM WILD RELATIVES.THEGOALOF THE PROJECT ISTO DEVELOP A SIMPLE, TARGETED, PRECISE AND FAST METHOD OF ALIEN GENE TRANSFER AND USE IT TO TRANSFER A HIGH LEVEL OF RESISTANCE TO AB. THESPECIFIC OBJECTIVESOF THE PROJECT ARE:IDENTIFY AND CONFIRM NOVEL SOURCES OF AB RESISTANCE AMONG THE WILD SPECIES,DEVELOP AND OPTIMIZE A NOVEL ALIEN GENE TRANSFER APPROACH IN CHICKPEA,DEVELOP BREEDER-FRIENDLY MARKERS FOR THE ALIEN GENE(S) CONTROLLING AB RESISTANCE, ANDFIELD TRIALS TO CONFIRM AB RESISTANCE AND OTHER AGRONOMIC TRAITS AMONG DEVELOP GERMPLASM.THE PROJECT WILL IDENTIFY AND CONFIRM ALIEN SPECIES ACCESSIONS SHOWING THE HIGHEST LEVEL OF AB RESISTANCE TO THE RACES PREVALENT IN THE MAJOR CHICKPEA GROWING AREAS OF US. ONCE IDENTIFIED, THE RESISTANCE FROM THE WILD RELATIVES SPECIES WILL BE TRANSFERRED TO A POPULAR CHICKPEA VARIETY USING A NOVEL ALIEN GENE TRANSFERRED METHOD THAT WILL BE OPTIMIZED BY THE PROJECT. THE TRANSFERRED AB RESISTANCE WILL BE CHARACTERIZED, AND BREEDER-FRIENDLY MARKERS WILL BE DEVELOPED FOR AB RESISTANCE. THE PROJECT RESOURCES INCLUDING AB RESISTANCE SPECIES, GERMPLASM AND MARKERS WILL BE SHARED WITH THE SCIENTIFIC COMMUNITY AND OTHER STAKEHOLDERS.$490,000
· FY2022 · National Institute of Food and Agriculture