Low Temperature Is Critical for Jujube Grafting Success in Frost-prone Northern New Mexico

The increased popularity of jujube (Ziziphus jujuba) combined with the difficulty of grafting have limited supplies of grafted trees in the United States. From 2011 to 2020, grafting was practiced for cultivar amplification after importation and cultivar trials in frost-prone northern New Mexico. Grafting success was related to not only grafting techniques but also climate factors. Bark grafting, whip/tongue grafting, and cleft grafting were commonly used in nurseries. Low temperatures had a critical role in jujube grafting success in marginal regions and were more important than the grafting technique. If frost occurs before or near the leafing time, then grafting should be delayed until the rootstocks are determined to be healthy and alive. If frost occurs after grafting, then grafting failure and/or thin and small plant percentages increased. If only branchlets appear after grafting, then pinching branchlets could stimulate new shoot growth.

Transcriptomic analysis of melon/squash graft junction reveals molecular mechanisms potentially underlying the graft union development

Oriental melon (Cucumis melo var. makuwa Makino) has become a widely planted horticultural crop in China especially in recent years and has been subjected to the grafting technique for the improvement of cultivation and stress resistance. Although grafting has a long history in horticulture, there is little known about the molecular mechanisms of the graft healing process in oriental melon. This study aims to reveal the molecular changes involved in the graft healing process. In the present work, anatomical observations indicated that the 2, 6, and 9 DAG were three critical stages for the graft healing and therefore, were selected for the subsequent high-throughput RNA-seq analysis. A total of 1,950 and 1,313 DEGs were identified by comparing IL vs. CA and CA vs. VB libraries, respectively. More DEGs in the melon scion exhibited abundant transcriptional changes compared to the squash rootstock, providing increased metabolic activity and thus more material basis for the graft healing formation in the scion. Several DEGs were enriched in the plant hormone signal transduction pathway, phenylpropanoid biosynthesis, and carbon metabolism. In addition, the results showed that concentrations of IAA, GA3, and ZR were induced in the graft junctions. In conclusion, our study determined that genes involved in the hormone-signaling pathway and lignin biosynthesis played the essential roles during graft healing. These findings expand our current understandings of the molecular basis of the graft junction formation and facilitate the improvement and success of melon grafting in future production.

Regulation of Phosphorus Supply on Nodulation and Nitrogen Fixation in Soybean Plants with Dual-Root Systems

Phosphorus (P) is an important nutrient affecting nodulation and nitrogen fixation in soybeans. To further investigate the relationship of phosphorus with soybean nodulation and nitrogen fixation, the seedling grafting technique was applied in this study to prepare dual-root soybean systems for a sand culture experiment. From the unfolded cotyledon stage to the initial flowering stage, one side of each dual-root soybean system was irrigated with nutrient solution containing 1 mg/L, 31 mg/L, or 61 mg/L of phosphorus (phosphorus-application side), and the other side was irrigated with a phosphorus-free nutrient solution (phosphorus-free side), to study the effect of local phosphorus supply on nodulation and nitrogen fixation in soybean. The results are described as follows: (1) Increasing the phosphorus supply increased the nodules weight, nitrogenase activity, ureide content, number of bacteroids, number of infected cells, and relative expression levels of nodule nitrogen fixation key genes (GmEXPB2, GmSPX5, nifH, nifD, nifK, GmALN1, GmACP1, GmUR5, GmPUR5, and GmHIUH5) in root nodules on the phosphorus-application side. Although the phosphorus-application and phosphorus-free sides demonstrated similar changing trends, the phosphorus-induced increases were more prominent on the phosphorus-application side, which indicated that phosphorus supply systematically regulates nodulation and nitrogen fixation in soybean. (2) When the level of phosphorus supply was increased from 1 mg/L to 31 mg/L, the increase on the P– side root was significant, and nodule phosphorus content increased by 57.14–85.71% and 68.75–75.00%, respectively; ARA and SNA were 218.64–383.33% and 11.41–16.11%, respectively, while ureide content was 118.18–156.44%. When the level of phosphorus supply was increased from 31mg/L to 61mg/L, the increase in the regulation ability of root and nodule phosphorus content, ARA, SNA, and ureide content were low for roots, and the value for nodules was lower than when the phosphorus level increased from 1 mg/L to 31 mg/L. (3) A high-concentration phosphorus supply on one side of a dual-root soybean plant significantly increased the phosphorus content in the aboveground tissues, as well as the roots and nodules on both sides. In the roots on the phosphorus-free side, the nodules were prioritized for receiving the phosphorus transported from the aboveground tissues to maintain their phosphorus content and functionality.

Clinical Evaluation of Surgical Orthodontic Procedure with Bone Grafts for Patients with Cleft Palate during Adolescence

Background: Cleft lip and palate is a congenital anomaly, presenting in a wide variety of forms and combinations. Successful cleft lip and cleft palate rehabilitation requires a multidisciplinary approach employing the skills of different specialists. Aims & Objectives: The aim of this paper was to present orthodontic preparation of patients prior to alveolar bone grafting & to review our findings in a group of patients treated by secondary and delayed bone-grafting procedures at our institution. Methodology: Thirty eight patients were examined for the type of cleft and the age at the time of examination. 10 patients were treated in our institution with presurgical orthodontics & operated by a delayed bone-grafting technique. Duration and type of expansion was noted at pre-operative, 2 months and 6 months. Crestal bone heights and the quality of the bone in the grafted areas was examined radiographically, along with presence of any fistulas. Results: All the patients demonstrated improved alar base and upper lip support, also better dental stability was seen in the region of cleft. Conclusion: All the patients included in this study appeared to benefit from the procedure with improved facial balance. In all ten patients the oronasal fistulas remained closed, hence was reported to be a success.

Alveolar Cleft Reconstruction Using Double Iliac Corticocancellous Bone Plates Grafting Technique in Mixed Dentition Phase

Objective The primary goal of maxillary alveolar cleft reconstruction in patients with cleft lip/palate at the phase of mixed dentition is to build bone in the cleft area which in turn allows closure of the oronasal fistula, establishes arch continuity, and improve maxillary stability. This study aimed to evaluate the double iliac corticocancellous bone plates grafting technique for initial alveolar cleft grafting. Design This prospective study was conducted on 12 consecutive patients with unilateral complete alveolar cleft and previous cleft lip and palate corrective surgery. Intervention For all patients, the iliac crest graft was harvested and cut into 2 cortical bone plates and adapted labially and palatally. Both plates were fixed with screws then the gap between the 2 plates was filled with cancellous bone. The grafted side was compared to the contralateral side 9 months postoperatively regarding labio-palatal alveolar width and bone density, while the 9 months postoperative graft height was compared to the immediate postoperative height using computed tomography scans. Results All grafted sides showed similarity to the contralateral sides regarding both alveolar width and bone density with minimal crestal bone resorption. Conclusion The double iliac corticocancellous bone plate grafting technique seems to be a reliable method for alveolar cleft reconstruction with adequate bone quality and contour.

Graft survival of Pinus engelmannii Carr. in relation to two grafting techniques with dormant and sprouting buds

Developing methods for successfully grafting forest species will be helpful for establishing asexual seed orchards and increasing the success of forest genetic improvement programs in Mexico. In this study we investigated the effects of two grafting techniques (side veneer and top cleft) and two phenological stages of the scion buds (end of latency and beginning of sprouting), in combination with other seven grafting variables, on the sprouting and survival of 120 intraspecific grafts of Pinus engelmannii Carr. The scions used for grafting were taken from a 5.5-year-old commercial forest plantation. The first grafting was performed on January 18 (buds at the end of dormancy) and the second on February 21 (buds at the beginning of sprouting). The data were examined by analysis of variance and a test of means and were fitted to two survival models (the Weibull’s accelerated failure time and the Cox’s proportional hazards model) and the respective hazard ratios were calculated. Survival was higher in the top cleft grafts made with buds at the end of latency, with 80% sprouting and an estimated average survival time of between 164 and 457 days after the end of the 6-month evaluation period. Four variables (grafting technique, phenological stage of the scion buds, scion diameter and rootstock height) significantly affected the risk of graft death in both survival models. Use of top cleft grafts with buds at the end of the latency stage, combined with scion diameters smaller than 11.4 mm and rootstock heights greater than 58.5 cm, was associated with a lower risk of death.

Development of a gRNA-tRNA Array of CRISPR/Cas9 in Combination with Grafting Technique to Improve Gene Editing Efficiency of Sweet Orange

Sweet orange is one of the most popular fruit crops worldwide. Traditional breeding approaches in sweet orange is impracticable due to the apomixis and long juvenility, making it difficult to obtain hybrids and selection of ideal genotypes. The development of targeted genome engineering technologies made it possible for the precise modification of target genes. Recently, a more efficient gene editing tool has been emerged based on the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (Cas) system (Bhaya et al. 2011). The development of CRISPR/Cas9 technology is promising to accelerate the process of genetic improvement in perennial crops.