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The study analyzed three genotypes of industrial hemp, Cannabis sativa L., under the aspect of fiber productivity indices in relation to plant parameters. The study took place in ARDS Lovrin, Romania. The genotypes Silvana (control), Teodora and Lv-300 were evaluated. The experiment took place under the conditions of a chernozem type soil, non-irrigated system. Several parameters and indexes were analyzed: total plant weight (TPW), stem length (SL), inflorescence length (IL), technical length (TL), middle stem diameter (MSD), dry sample weight (DSW), dry fiber content (DFC), pure fiber weight (PFW), and technical fiber (TF). The DFC index showed positive correlations with SL (r=0.708***), with MSD (r=0.712***), with DSW (r=0.739***), with TPW (r=0.546**), and with TL (r=0.399*). The PFW index showed negative correlations with TPW (r=-0.493**) and with DSW (r=- 0.373*). Technical fiber (TF) showed very strong, positive correlations with PFW (r=0.999***) and negative correlations with other parameters (e.g. with TPW, r=-0.493**, with DSW, r=-0.373*). From the comparative analysis of Teodora in relation to Silvana, average values TFT=31.355 (Teodora) and TFS=28.388 (Silvana) resulted, and the differences showed statistical certainty (t=2.5948, with p=0.013; U=72, p=0.0045; p<0.05). From the comparative analysis of Lv-300 in relation to Silvana (control), mean values TFT=29.357 (Lv-300) and TFS=28.388 (Silvana) resulted, but the differences did not show statistical certainty (t=0.763, with p=0.451; U=117, p=0.158; p>0.05). The regression analysis led to equations and graphic models that described the variation of fiber productivity indices in relation to plant biometric parameters. [ABSTRACT FROM AUTHOR]

The study comparatively analyzed the productivity level of 48 commercial sunflower hybrids, under the specific crops conditions of the Western Plain of Romania. The field experiment took place within ARDS Lovrin, agricultural year 2021-2022. 27 hybrids from the Imazamox class (IH; IH1 to IH27) and 21 hybrids from the Tribenuron Methyl class (TMH; TMH1 to TMH21) were cultivated. The cultivation of the 48 hybrids was carried out under the conditions of a chernozem type soil, and non-irrigated system. In the case of Imazamox class hybrids (IH), the production varied between 2012.47 kg ha-1 (IH4) and 3,545.08 kg ha-1 (IH1, and IH23). In the case of hybrids from the Tribenuron Methyl class (TMH), production varied between 2,437.64 kg ha-1 (TMH17) and 3,713.15 kg ha-1 (TMH4, and TMH19). Based on the production data recorded for each hybrid, the average value was calculated for each class of hybrids (IH-Avg=3,038.13 kg ha-1, TMH-Avg=3,287.98 kg ha-1). In order to verify whether there are differences between the two groups IH (N=27) and TMH (N=21) regarding the recorded production, the Null Hypothesis (H0) was defined. The application of the t-test for Equality of Means, led to the value of t=2.302 with p=0.02. Additionally, the non-parametric Mann-Whitney test was applied. The U=180 value with p=0.03 also indicated significantly different productions between the related series of the two classes of hybrids. The increase in production (kg ha-1, %) was calculated for each class of hybrids (ΔIH, ΔTMH) and a classification was made within each class. The cluster analysis facilitated the clustering of sunflower hybrids in relation to the recorded production. [ABSTRACT FROM AUTHOR]

Imaging analysis (UAV images) was used to evaluate a corn crop under hydric stress conditions. From the analysis of the series of images (June 29 - T1, July 20 - T2, year 2022) the values of the RGB parameters resulted. Suplementary the luminance (Lum), normalized values (rgb), values in the HSB system, and INT, NDI and DGCI indices, were determined. The correlation analysis identified 18 very strong correlations between the parameters considered at the time of T1, and 10 very strong correlations at the time of T2. The PCA analysis led to the classification of the components: seven components in PC1 (R = -9.93 the highest value) and three components in PC2 (Lum = 0.970 the highest value) at the time of T1; four components in PC1 (r = -0.990 the highest value) and four components in PC2 (Lum = 0.949 the highest value) at time T2. The differences between the series of parameters, at the moments T1 and T2, were confirmed by values U = 18, p = 0.017 in the case of parameter G; U = 10, p = 0.0028 in the case of the B parameter; t = 9.4202, p < 0.01 in the case of NDI; t = 9.2066, p<0.001, U = 1, p < 0.001 in the case of INT; t = 9.3176, p < 0.001 in the case of DGCI; t = 7.5581, p < 0.001, U = 3, p < 0.001 in the case of Lum. [ABSTRACT FROM AUTHOR]