Bermudagrass (Cynodon dactylon (L.) Pers.) turf loss due to severe cold in transitional climates is a major concern. To overcome this problem, warm-season grass is often overseeded with a cool-season turfgrass. In this study, modeling and efficient nutrient management were used to evaluate this problem. A three-factor and five-level central composite rotatable design (CCRD) with a simulation of a regression model was used to optimize fertilization rates. The study investigated the combined effects of fertilization with nitrogen (N), phosphorus (P), and potassium (K) on both the morphological and physiological attributes and on the integrated turf performance (ITP) of overseeded perennial ryegrass (Lolium perenne). Fertilization with N and P significantly increased turf height, density, color, fresh and dry weights, while N, P, and K significantly affected turf cover, quality and winter-kill. The Spring transition was delayed by fertilization with N and P, and accelerated by fertilization with K. Photosynthesis (Pn), transpiration (Tr), and stomatal conductance (Gs) were considerably enhanced by fertilization with N, P and K. Protein levels and total chlorophyll levels were substantially increased by fertilization with N and P and with N, P, and K, respectively, during a two-year period. During two separate experiments conducted during two consecutive years, the optimal combinations of N, P, and K were N: 30, P: 24, K: 9, and N: 30, P: 27, K: 6 g m-2. The major conclusion of this study is that a balanced nutrient application utilizing N, P, and K is key to enhancing the winter performance of perennial ryegrass.

The lotus (Nelumbo nucifera Gaertn.) is one of the most economically and ornamentally important perennial aquatic plants. Plant architecture is an important trait for lotus classification, cultivation, breeding, and applications. In this study, traits representing plant architecture were measured in 390 lotus germplasms for 3 years. According to the phenotypic distribution, 21 large architecture (LA) and 22 small architecture (SA) germplasms exhibiting extreme phenotypes were selected as representatives of plant architecture. Microscopy analyses revealed that LA lotuses possessed far more vertical cells and longer cell lengths than SA lotuses, and there was a closer linear relationship between vertical cell number and plant architecture than cell length and plant architecture. Furthermore, based on whole genome re-sequencing data from 10 LA and 10 SA lotus germplasms, fixation index (F_ST) genome scan identified 11.02 Mb of genomic regions that were highly differentiated between the LA and SA lotus groups. Chi-square test revealed that 17,154 single nucleotide polymorphisms (SNPs) and 1,554 insertions and deletions (InDels) showed distinct allelic distribution between the LA and SA lotus groups within these regions. A total of 126 variants with distinct allelic distribution in the highly differentiated region were predicted to cause amino acid changes in 60 genes. Among the 41 genes with functional annotation, the expression patterns of six genes involved in cell division and cell wall construction were confirmed using quantitative reverse-transcription PCR (qRT-PCR). In addition, 34 plant architecture-associated InDel markers were developed and verified in the remaining 11 LA and 12 SA lotus plant architecture representatives. This study identified promising functional markers and candidates for molecular breeding and will facilitate further elucidation of the genetic mechanisms underlying plant architecture in the lotus.

Bermudagrass (Cynodon dactylon (L.) Pers) turf is the most widely used turfgrass in urban landscapes. Large amounts of fertilizer are usually applied for maximum turf performance, while relatively little attention has been paid to efficient nutrient management of bermudagrass turf. The design opted for was a 3-factor and 5-level Central Composite Rotatable Design (CCRD) consisting of 24 experimental runs in the greenhouse with response surface methodology (RSM) and simulated regression modeling. The experiment covered in this study was carried out at Sichuan Agricultural University with the objectives of understanding the interactive effects of nitrogen, (N), phosphorus (P), and potassium (K) fertilization on the bermudagrass integrated turf performance (ITP) and optimizing the amount of N, P, and K required for optimum turf performance during establishment. The qualitative and quantitative relationships between bermudagrass and fertilization significantly affected the ITP. The N, P, and K Fertilization significantly influenced the percent grass cover, turf height, shoot dry weight, root dry weight, and total chlorophyll content. Fertilization with N and P significantly enhanced the tiller length, turf density, color, and total protein levels. Root length was augmented with the application of P and K. We found that 3-D surface plots indicated significant interactive effects of NP, NK, and PK on the ITP. A simulation optimization and frequency analysis indicated that the optimal combined amounts of these nutrients were N: 26.0–27.6 g m⁻², P: 24.2–26.4 g m⁻², and K: 3.1–5.0 g m⁻² during the establishment phase. The results suggest that optimized fertilization is key to sustainable nutrient management of bermudagrass integrated turf performance.

It is generally assumed that compounds are emitted from flowers in order to attract and guide pollinators. Due to the invisibility and the highly variable nature of floral scent, no efficient and...