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Biology subjects

Vanzetti, L. S.

Publications and source records attributed to Vanzetti, L. S..

4 recordsLinked to original sources

Enhancing wheat yield potential through the QFFE.perg-5A and QFEm.perg-3A associated to spike fruiting efficiency: Insights from plot-level analysis

Wheat (Triticum aestivum L.) is a key global crop, essential for food security. To enhance its productivity this study focused on two quantitative trait loci (QTL), QFFE.perg-5A and QFEm.perg-3A, previously associated with fruiting efficiency at the spike level. We extended the analysis to the plot level to evaluate their impact on yield, thousand grain weight, and related traits, using a double haploid population of 102 lines in three environments. The results showed an epistatic interaction between a QTL for spike dry weight and grain number per spike. QFFE.perg-5A showed no interaction with the environment, increasing fruiting efficiency (13-15%), grain number per spike (7%), and spike number per unit area (9%), leading to an 8% rise in grain number per unit area and a 5% yield increase. In contrast, QFEm.perg-3As impact depended on the environment. This study connects spike-level QTL analysis with plot-level effects, providing valuable insights for breeding programs to improve wheat varieties with desirable traits and increased productivity.

genetics↗

Wheat plant height locus RHT25 encodes a PLATZ transcription factor that interacts with DELLA (RHT1)

Plant height is an important agronomic trait with a significant impact on grain yield, as demonstrated by the positive effect of the REDUCED HEIGHT (RHT) dwarfing alleles (Rht1b) on lodging and harvest index in the "Green Revolution" wheat varieties. However, these gibberellic acid (GA) insensitive alleles also reduce coleoptile length, biomass production, and yield potential in some environments, triggering the search for alternative GA-sensitive dwarfing genes. Here we report the identification, validation and characterization of the gene underlying the GA-sensitive dwarfing locus RHT25 in wheat. This gene, designated as PLATZ-A1 (TraesCS6A02G156600), is expressed mainly in the elongating stem and developing spike and encodes a plant-specific AT-rich sequence- and zinc-binding protein (PLATZ). Natural and induced loss-of-function mutations in PLATZ-A1 reduce plant height and its over-expression increases it, demonstrating that PLATZ-A1 is the causative gene of RHT25. PLATZ-A1 interacts physically and genetically with RHT1 (DELLA), and both genes have stronger effects on plant height in the presence of the wildtype than in the presence of the mutant allele of the other gene. These results suggest that PLATZ1 can modulate the effect of DELLA on wheat plant height. We identified four natural truncation mutations and one promoter insertion in PLATZ-A1 that are more frequent in modern varieties than in landraces, suggesting positive selection during wheat breeding. These mutations can be used to fine-tune wheat plant height and, in combination with other GA-sensitive dwarfing genes, to replace the GA-insensitive Rht1b alleles to search for grain yield improvements beyond those of the Green Revolution varieties. Significance StatementWe have identified and characterized a previously unknown gene controlling plant height in wheat and named it PLATZ1. Mutations in PLATZ1 reduce plant height while its overexpression results in taller plants. PLATZ1 is expressed mainly in elongating stems and developing spikes and interacts physically and genetically with the "Green Revolution" dwarfing gene REDUCED HEIGHT 1 (RHT1). We discovered five natural mutants in the A genome copy of PLATZ1 in common wheat that have been favored during breeding, suggesting an overall positive effect on wheat performance. These mutations can be used to fine-tune wheat plant height and, eventually, to replace the RHT1 dwarfing alleles that impose limitations on planting depth and grain yield potential in some environments.

plant biology↗

Increasing Grain Yield in Bread Wheat by Selection for High Spike Fertility Index

Spike fertility index (SF) has been proposed as a promising selection criterion for increasing grain yield (GY) in bread wheat. Here, changes in GY and related traits after simulated selection (10% intensity) for high SF or high GY per se were assessed in two RIL populations: (I) Avalon/Glupro and (II) Baguette 10/Klein Chaja, and in (III) advanced lines from a breeding program. Grain yield, SF, grain number per unit area (GN), grain weight (GW), test weight (TW) and grain protein content (GPC) were determined. Regardless of the environmental conditions, simulated selection for high SF always resulted in GN increases (between 1.6 and 27.4%). Average GY increase observed after selection for high SF (11.5%; N=10; SEM=5.8) did not differ (p=0.92) from the average GY increase observed after selection for GY per se (11.8%; N=10; SEM=4.9). Grain weight, GPC and TW tended to decrease with selection for high SF; however, these trade-offs might be avoided by concurrent selection. Our findings validate the use of SF as a selection criterion for increasing grain yield in bread wheat.

plant biology↗

Mapping QTL for spike fertility related traits in two double haploid wheat (Triticum aestivum L.) populations

In breeding programs, the selection of cultivars with the highest yield potential consisted in the selection of the yield per se, which resulted in cultivars with a higher grain number per spike (GN) and occasionally higher grain weight (GW) (main numerical components of the yield). This task could be facilitated with the use of molecular markers such us single nucleotide polymorphism (SNP). In this study, quantitative trait loci (QTL) for GW, GN and spike fertility traits related to GN determination were mapped using two double haploid (DH) populations (Baguette Premium 11 x BioINTA 2002 and Baguette 19 x BioINTA 2002, BP11xB2002 and B19xB2002). Both populations were genotyped with the iSelect 90K SNP array and evaluated in four (BP11xB19) or five (B19xB2002) environments. We identify a total of 305 QTL for 14 traits, however 28 QTL for 12 traits were considered significant with an R2 > 10% and stable for being present at least in three environments. There were detected eight hotspot regions on chromosomes 1A, 2B, 3A, 5A, 5B, 7A and 7B were at least two major QTL sheared confident intervals. QTL on two of these regions have previously been described, but the other six regions were never observed, suggesting that these regions would be novel. The R5A1 (QSL.perg-5A, QCN.perg-5A,QGN.perg-5A) and R5A.2 (QFFTS.perg-5A, QGW.perg-5A) regions together with the QGW.perg-6B resulted in a final higher yield suggesting them to have high relevance as candidates to be used in MAS to improve yield. Author contribution statement Key message28 stable and major QTL for 12 traits associated to spike fertility, GN and GW were detected. Two regions on 5A Ch., and QGW.perg-6B showed direct pleiotropic effects on yield.

plant biology↗