true x seeds

Always ignored, exists for compatibility.

Preserve order dependencies in the dataset ordering, when shuffle=False : all samples from class k in some test set were contiguous in y, or separated in y by samples from classes other than k.

Generate test sets such that all contain the same distribution of classes, or as close as possible.

Parameters X array-like of shape (n_samples, n_features)

The training set indices for that split.

random_state int, RandomState instance or None, default=None

Be invariant to class label: relabelling y = ["Happy", "Sad"] to y = [1, 0] should not change the indices generated.

Whether to shuffle each class’s samples before splitting into batches. Note that the samples within each split will not be shuffled.

Always ignored, exists for compatibility.

“It went on for months and months and months,” she said. “I just stopped opening them.” Last July, when she heard that others were receiving seeds, she contacted the Louisiana agriculture department. That call didn’t go the way it was supposed to. “They were like, ‘Oh, it’s a hoax … Plant them or toss them, do what you want,’” Alwhite recalled. “That’s Louisiana for you.”

Over the next few weeks, these British gardeners became exasperated. Amid plenty of thoughtful debate and the occasional xenophobic comment (less than 10 hours after Westerdale’s post, someone wrote: “I reckon it’s some kind of covert biological thing from China that will affect all our plant life and we’ll all die of starvation, then China will take over the world”), there was a sense of frustration that something important was going on and no one was listening. People in “Veg gardening UK” and other groups contacted the British agricultural authorities. They contacted celebrity gardeners and members of Parliament. They contacted the media. One person, tweeting under the name Tinkerpuss I will NOT be silenced! (apparently a beautician named Charlotte), was particularly vociferous, firing urgent messages at British newspapers, to no effect.

T hese “sinister seed packs” were also arriving at American homes—the U.S. Department of Agriculture would retroactively date the earliest related package that it was aware of to June 2. Aside from a few bemused comments online, though, there’s little indication that anyone took too much notice until Lori Culley, a grandmother in Tooele, Utah, just west of Salt Lake City, succeeded in sounding the alarm.

And that’s when things got really weird.

John Roberts, a retired railway worker who lives 100 miles to the south, replied within the hour; he’d gotten some seeds the previous week. He’d called the local police, who came and picked them up, telling Roberts they’d investigate the seeds and then burn them. Other stories followed.

True x seeds

Struik PC, Wiersema SG (1999) Seed potato technology. Wageningen Pers, Wageningen.

In both years, the tuber DM% of genotype H04 was higher (22.5% and 22.0%) than the DM% of genotype H03 (18.2% and 18.0%). Because the total tuber DW did not differ between genotypes in both years, the higher total FW of tubers in genotype H03 compared with H04 can be explained by a higher water content of the tubers in H03.

Almekinders CJM (1995) On flowering and botanical seed production in potato (Solanum tuberosum L.). Dissertatoin, Wageningen University

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Seedlings were transplanted by hand in the field on 23 May 2017 and 17 May 2018, 4 – to 5-cm deep in ridges, ensuring that the top of the peat moss substrate was covered with about 1 cm of soil. Plant distances between rows and plants within rows were 75 × 20 cm. Gross and net plot dimensions for individual sub-plots were 3.00 × 1.80 m and 1.50 × 1.00 m, respectively, resulting in a net plot area of 1.5 m 2 which included 10 plants. Measurements and observations were always made at net plot level.

The current study only showed minor effects of hilling on the yield and yield components of transplanted experimental hybrid seedlings. However, when improved hybrid cultivars are developed, cultivar-specific responses to hilling and transplanting depth will be important aspects to study (cf. Kouwenhoven 1970). Meanwhile, studies on the potential of novel systems to cultivate hybrid potato should focus on other crucial aspects of the agronomy of such systems, including transplanting time, harvesting date and population density of transplants.

Temperature, precipitation, applied irrigation and major field events during the field growing period in 2017 and 2018. (a) Minimum (T-Min) and maximum (T-Max) daily temperatures and the temperature sum (T-Σ), Tbase = 0 °C; (b) accumulated amount of water received in the fields; (c) daily amount of water received by precipitation and irrigation in 2017 and (d) in 2018; (e) major field activities. (1) Haulm removal was 7 days prior to tuber harvest

Statistical Analysis

Wohleb CH, Knowles NR, Pavek MJ (2014) Plant growth and development. In: Navarre R, Pavek MJ (eds) The potato: botany, production and uses. CABI, Boston, pp 64–82.

The hybrid true seeds were sown 5 weeks prior to field transplanting in 104-plug trays (32 × 52 cm, Horticoop, Bleiswijk) with cells of 2.5 × 2.5 × 3.8 cm (w × l × h) filled with 23.75 ml peat moss substrate. One seed was sown by hand on top of the substrate. Seedlings were grown for 4 weeks in a greenhouse nursery at 75% relative humidity, with day/night temperature set at 18/16 °C, and a 16-h photoperiod ensured by Son-T 600 W lamps which switched on when radiation dropped below 120 W m −2 . Seedlings were irrigated every second day to avoid water-limiting conditions. Four weeks after sowing, the nursery trays were placed in a screenhouse with open sides for a 1-week hardening-off period. Selection of usable transplants was carried out 1 day prior to transplanting using the following criteria: aboveground height between 7 and 12 cm with 5 to 8 fully developed leaves.